The series was commissioned by Warner Bros. Television in 2007 as a presentation lasting 14–20 minutes. Alex O'Loughlin, Shannon Lucio, Rade Šerbedžija and Amber Valletta were cast in the lead roles, and Rod Holcomb was hired as director. David Greenwalt joined the staff in May 2007 as showrunner and executive producer with Joel Silver; however, health reasons forced Greenwalt to leave the series. All of the original actors, apart from the male lead role, were recast in June 2007 with Sophia Myles, Jason Dohring and Shannyn Sossamon. A retooled, full-length pilot for television audiences was then shot.

Moonlight was premiered on September 28, 2007, and shown on Friday nights on CBS. Although received poorly by critics, the pilot finished first among total viewers and adults aged 18–49 for its night. The series received generally negative reviews, and averaged 7.57 million American viewers per episode. Many critics criticized the acting and the writing; however, Jason Dohring's performance was praised. Moonlight went on hiatus due to the 2007–2008 Writers Guild of America strike, but returned with four new episodes once the strike ended. On May 13, 2008, CBS announced that Moonlight was officially canceled.

The pilot introduces Mick St. John, a private investigator who has been a vampire for over fifty years. He meets Beth Turner, a reporter for the online newspaper BuzzWire, at the scene of the murder of a young woman. Mick and Beth begin investigating the crime together, helping each other to catch the killer. Flashbacks to 22 years ago show a domestic fight between Mick and his ex-wife Coraline Duvall over a kidnapped girl. Mick sets fire to the house and rescues the girl, leaving Coraline to the fire. It is revealed that the little girl has grown up to be Beth, and that Mick has tried to watch over her and keep her safe over the years. In the present, Beth discovers that Mick is a vampire, and Mick reveals how one becomes a vampire and tells her the story of how he was turned by his bride, Coraline, on their wedding night.

Beth asks Mick to help her friend Morgan find her stolen cameras. When he meets her, Mick is completely shocked; Morgan is identical to his ex-wife, Coraline. He becomes even more confused when his vampiric sense of smell tells him that Morgan is human. Mick tries to expose Morgan as Coraline, but finally comes to believe that she is a doppelgänger when he sees that she does not have the fleur de lis tattoo on her shoulder as Coraline did. When alone, Morgan scrubs away the heavy makeup that has been covering the tattoo. Beth snoops through Mick's property, and finds out Mick was the one who protected her as a little girl when she was kidnapped. Morgan goes with Mick to his apartment to clean up after almost getting hit by a car. Mick joins her in the shower and finally sees the tattoo on her shoulder, revealing her identity as Coraline. When Beth learns that Morgan is really Coraline, the lady who kidnapped her as a child, she goes to Mick's apartment and stabs her with a wooden stake, narrowly missing her heart, not realizing that she has become human. Coraline goes to hospital, but recovers and leaves after being revealed to be a vampire again. Beth's boyfriend Josh is kidnapped by a dangerous Los Angeles–based gang. Mick and Beth witness the event and drive after him, but Josh is shot. Beth realizes that Josh is dying, and begs Mick to turn him into a vampire; he refuses and Josh dies. While putting Josh's affairs in order, Beth discovers that Josh was about to propose to her.

Mick encounters two vampires who are looking for Coraline. Once they leave, Mick visits his vampire friend Josef, who tells him that one of them was Lance (Jason Butler Harner), a rich and powerful vampire. Mick finds Coraline at a storage facility working on a compound for the vampire cure. Coraline explains that during the French Revolution there were seven siblings of royal blood who were vampires, two of whom were Lance and Coraline. She then uses the compound to cure Mick's vampirism, although Lance arrives and takes her away. Mick enjoys life as a human, although the cure is only temporary. Beth's boss at BuzzWire is killed, and a new assistant district attorney named Benjamin Talbot (Eric Winter) investigates the murder. Mick and Beth discuss the problems of having a romantic relationship, and although they end up kissing, Mick tells her he needs time to figure things out. Photos of Mick getting hit by a vehicle find their way into the hands of Talbot. Mick and Beth decide to start a romantic relationship, and go to a restaurant for their first date. When Beth quits her job at BuzzWire and becomes unemployed, Talbot offers her a job as a civilian investigator. Talbot receives a list of names of all the vampires in the area, including Mick, from an unknown source. Beth tells Mick that she cannot continue to date him because of their vampire-human situation, but Mick says that he loves her and they kiss.

The conventions of Moonlight are based, in part, on a unique mythology. Some parts of the mythology that are common include a sire, that is the vampire who turns a human into a vampire; though in the show the sire must teach him or her how to live as one. A vampire's bite is not enough to turn a human into a vampire; the human, when near death, must drink the sire's blood or have vampire blood in his or her system at the moment of death. The process of vampirization also affects their genetics, causing their DNA to be fundamentally altered to suit their bodies' new state. This makes genetic testing between vampires and their human relatives impossible unless the vampire has a sample of their own human DNA from before they were turned, such as a lock of hair. They must consume human blood to survive. They also develop psychic powers and can glimpse the future and the past. This ability, along with their night vision, is an extension of their heightened senses. Daylight does not kill vampires, but does make them progressively weaker. Silver and fire are toxic, whereas garlic, holy water and crucifixes are benign. A vampire's image cannot be captured with analogue cameras containing silver emulsion in the film; digital cameras are able to capture an image because they do not use silver emulsion. Though undead, vampires have a pulse, are not cold-blooded (but still don't produce body heat as seen in episode 11 so that heat signature cameras won't see them), and cannot turn into a bat. The only ways to kill them are by decapitation or burning; a stake through the heart is painful but only causes paralysis. Moonlight vampires have many of the preternatural abilities described in vampire mythology; they have superhuman strength and speed, they heal rapidly from any wound, they can defy gravity to a limited degree to perform parkour feats, their bite has hypnotic effects on weak-minded humans, and they are immortal. Their powers increase as they get older. Their blood has drug-like effects when consumed by humans; causing euphoria and temporarily heightened senses.

• Alex O'Loughlin portrays Mick St. John, a private investigator who was turned into a vampire on the night of their wedding by his bride, Coraline. Mick is 85 years old; unlike other vampires, he has standards and does not hunt women, children, or innocents. Although he realizes that he has feelings for Beth, he is reluctant to continue a romantic relationship with her, knowing that being a vampire would hinder any sort of normal life. He is shown to be unusually mature and physically strong for a vampire of his age.
• Sophia Myles portrays Beth Turner, an internet reporter and Mick's love interest. Beth has some memories of being rescued from a kidnapper by Mick 22 years previously, but does not initially realize that Mick is the same man. At the beginning of the series, she is dating an assistant district attorney, Josh Lindsey (Jordan Belfi), but later develops a romantic relationship with Mick, whom she begins dating after Lindsey's death.
• Jason Dohring portrays Josef Kostan, a 410-year-old vampire and Mick's mentor and friend. Josef is a businessman who indulges himself with luxuries, from an expensive house to the company of numerous beautiful women who are more than happy to sate his desire for blood. Josef is Mick's second sire, ending the latter's brief stint as a human.
• Shannyn Sossamon portrays Coraline Duvall, St. John's ex-wife and original sire. A courtesan in early 18th century France, she is approximately 340 years old. After turning Mick into a vampire, the couple became estranged and Coraline was presumed dead for more than twenty years. When she returns under the pseudonym Morgan, she appears to be completely human and claims to have a cure for vampirism, which Mick becomes desperate to obtain.

• Jacob Vargas as Guillermo Gasol, a morgue worker who steals blood from dead bodies for himself and other vampires.
• Brian J. White as Lieutenant Carl Davis, one of Beth's contacts and a friend of Mick.
• Jordan Belfi as Josh Lindsey, Beth's boyfriend who works in the district attorney's office. Josh is killed by a member of the MS-13 gang.
• Tami Roman as Maureen Williams, Beth's boss at BuzzWire. Maureen is killed by a vampire over one of her stories.
• Kevin Weisman as Steve Balfour, a friend of Beth and co-worker at BuzzWire.
• David Blue as Logan Griffin, a vampire computer hacker and technology-obsessed recluse who Mick often goes to for help.
• Erika Ringor as Officer Theresa Novak, a police officer who sometimes gets involved with Mick and Beth's affairs.
• Eric Winter as Benjamin Talbot, an assistant district attorney who offers Beth a job.
• Nate Mooney as Ryder England, a vampire hacker employed by Josef Kostan who helps Mick and Beth find a vampire draining and killing escorts.

Trevor Munson conceived the character of Mick Angel in 2004 and spent two and a half years writing a novel featuring the character. The story was adapted into a feature film script, and Bruce Willis was considered as a possibility for the lead role. The script was shown to Nina Tassler at CBS, who paired Munson with Ron Koslow, creator of Beauty and the Beast, to rewrite the script as a television series. The series was titled Twilight, and Koslow and Munson wrote the pilot, which Warner Bros. Television initially commissioned as a presentation lasting 14–20 minutes in January 2007. Joel Silver and Gerard Bocaccio were hired to be executive producers on the project under the former's production banner, Silver Pictures, in the same month. Alex O'Loughlin and Shannon Lucio were cast in the presentation, and Rod Holcomb was hired as director. The project was renamed Moonlight when picked up by CBS on May 14, 2007, prior to the upfronts. David Greenwalt, creator of Miracles and co-creator of Angel, joined the staff in May 2007 as showrunner and executive producer alongside Silver. CBS had hired Greenwalt during the pilot process to restructure the original concept by Koslow and Munson, but health reasons forced Greenwalt to leave the series, and Chip Johannessen took over showrunner duties in August 2007.

During Greenwalt's restructuring of the pilot, all of the original actors save for the male lead role of Mick St. John were recast in June 2007: Shannon Lucio, Rade Šerbedžija and Amber Valletta were originally cast in the roles of Beth Turner, Josef Kostan and Coraline Duvall respectively before Sophia Myles, Jason Dohring and Shannyn Sossamon replaced them. With this almost entirely different cast, a retooled, full-length pilot for television audiences was re-shot. Joel Silver approached Dohring "out of the blue and said, 'There's a role, and I'm making it younger'". Dohring read two pages of script featuring Josef, and was interested by the character's "dark" and "sharp" personality. Dohring had to go through the normal audition process and was not sure he would have gotten the role without Silver, who had "pushed it all the way through to the end".

Munson explained that the goal of the casting changes was "to lighten the show up a bit". He believed the changes granted the studio and network's wish to "make it a little younger and hipper". O'Loughlin felt that the whole cast's becoming "a little bit younger" especially affected the character Josef, as the originally chosen actor, Šerbedžija, was twice Jason Dohring's age. The creators and the network were concerned that Josef, whose relationship with Mick was important, would appear as more of a "father figure" rather than as a friend. O'Loughlin supported the recasting of Josef with a younger actor due to the resulting "level of ease in that age difference".

To promote the series, Silver and the main cast attended the Comic-Con International on July 27, 2007, where the series was featured. Moonlight premiered on September 28, 2007, airing on Friday nights at 9:00/8:00c on CBS, following Ghost Whisperer. Internationally, CTV began airing the series in Canada in simulcast with the American broadcast; Living began airing the series in the United Kingdom on February 19, 2008; and Nine Network in Australia began airing Moonlight on December 12, 2007, although it stopped showing the series after the eighth episode. The series finale aired on May 16, 2008, in the United States. The Sci Fi Channel began airing repeats of the series on January 23, 2009, on Fridays at 9 pm/ET. The series averaged one million viewers per episode on the Sci Fi Channel, making it one of the better-performing acquired series of the channel in recent years. Warner Home Video released the complete first season on DVD on January 20, 2009. On May 5, 2010, it was announced that reruns of the series would be paired with The Vampire Diaries repeats throughout the summer on The CW.

Les Moonves, President of CBS, stated on December 4, 2007, that Moonlight was likely to return for a second season. Due to the 2007–2008 Writers Guild of America strike, production of the series was halted by December 19, 2007, and only twelve episodes of the original thirteen-episode order were produced. Once the Writers' Strike ended, CBS announced that Moonlight would return on April 25, 2008, with four new episodes, to be part of the series' first season. On May 13, 2008, CBS announced that Moonlight was officially cancelled. Following the CBS cancellation, Warner Bros. Television inquired with other outlets about their interest in the series. One of the outlets approached was Media Rights Capital, which is responsible for The CW's Sunday night programming, although it decided not to acquire the series. It was later reported that Syfy was considering picking up the series. Writer and executive producer Harry Werksman said that "talks" were under way for a second season, and noted the possibility of a film. On June 23, 2008, James Hibberd of The Hollywood Reporter reported that efforts to sell Moonlight to another network had failed, and that the series was permanently cancelled.

Syfy acquired the rights to air the show. In summer 2010, The CW announced that it would air repeats of the show on Thursdays at 9:00 pm following The Vampire Diaries encores. The first episode aired on June 3 and attracted 1.41 million viewers and a 0.5 rating in adults aged 18–49. The repeat of the finale episode aired on August 26, 2010, and then the network removed it from the schedule.

Moonlight attracted a loyal and devoted fan base which included internet communities. Fans Christine Contilli, Elizabeth McGinnis, and Barbara Arnold coordinated with the American Red Cross, CBS, and Warner Bros for a series of charity blood drives involving 33 states, and Alex O'Loughlin became a national spokesman for the charity. The series averaged 7.57 million American viewers per episode, ranking 89 out of 281 in the 2007–08 ratings. The pilot, "No Such Thing as Vampires", finished first among total viewers and adults aged 18–49 for its night, and was seen by 8.54 million American viewers. By comparison, the series finale, "Sonata", was watched by 7.47 million viewers upon its original broadcast, making it the 41st-most watched episode of the week. Moonlight was the 90th-most watched series of the 2007–2008 Television season with 7.53 million viewers.

Reviews were generally negative for the pilot, and the early episodes. Metacritic gave the pilot a Metascore of 38 out of 100, signifying generally negative reviews. Tim Goodman of the San Francisco Chronicle considered the series to be "the worst new fall show". The writing was criticized as "ponderous", and having "familiar, conventional plots". The dialogue was described by Maureen Ryan of the Chicago Tribune as "groan-inducing". The acting of the pilot was criticized as "sub-par" and "woeful". Matthew Gilbert of The Boston Globe depreciated the chemistry between O'Loughlin and Myles as "artificial", and said that they "exchange lines of dialogue with a stilted rhythm and no natural flow". O'Loughlin was described as a "flatliner", and "passable in the lead role". Not all reviews, however, were as negative. Kara Howland of TV Guide gave the pilot a positive review, and thought it was a "solid start". Travis Fickett of IGN praised the actors, however, and felt that O'Loughlin did "a decent job", and that Myles was "perhaps the most promising aspect of the show". Ryan commended Myles as "reasonably good". Several critics praised Jason Dohring's portrayal of Josef. One said that he gave the series "a small burst of energy", while another said that he made it "crackle with a bit of wit". Dohring was described as "a welcome presence", and one critic wished for "a bit more screen time".

Reviews of the second episode were generally more positive than the pilot. Travis Fickett of IGN described the episode, and the series as a whole, as "vampire mediocrity with a slight hint of potential". He compared the episode to the television series Angel, saying it was "weaker on virtually every front". Jen Creer of TV Squad criticized the writing, but said she felt that Sophia Myles was doing a "decent job of developing her character and embracing the material". Carl Cortez of iFMagazine.com said this episode improved "leaps and bounds", and was a "step in the right direction". He gave the episode a 'C' rating, saying the direction was "lifeless" and the acting was "stilted". AOL TV placed the show in its list of TV's Biggest Guilty Pleasures. Rotten Tomatoes gives the series a critic rating of 22%.

• People's Choice Award for Favorite New TV Drama, 2008
• Saturn Award for Best Television Series Release on DVD, 2009 (awarded by the Academy of Science Fiction, Fantasy & Horror Films)

• Vampire film
• List of vampire television series

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