Teddy Mitchell is a fictional character from the BBC soap opera EastEnders, played by Roland Manookian. Teddy was introduced by executive producer Chris Clenshaw in episode 6931, broadcast on 26 June 2024, as the head of an extension to the soap's Mitchell family. The character debuted alongside his sons Harry (Elijah Holloway) and Barney (Lewis Bridgeman), and was initially billed as a charming and strong-willed, but cunning presence. The character, alongside his two sons, were first announced on 6 June 2024. Throughout his time on the serial, Teddy has been depicted as a charming and confident father who is fiercely protective over his sons, but with a more sinister side hidden beneath. After being cast, Manookian was both surprised and excited to have received the role, describing Teddy as an interesting part to "get [his] teeth into".

His storylines in the series have included his arrival in search of his father Stevie Mitchell (Alan Ford) and his discovery that Stevie had another family, his relationship with Sharon Watts (Letitia Dean), igniting a feud between the Mitchells and the Panesar family, and the arrival of his estranged wife Nicola Mitchell (Laura Doddington). Teddy's enigmatic personality attracted praise from both viewers and critics.

After Stevie Mitchell (Alan Ford) is hospitalised, Teddy is contacted as he is the next of kin and he arrives at the hospital with his sons Harry Mitchell (Elijah Holloway) and Barney Mitchell (Lewis Bridgeman). They explore Walford, where Teddy breaks into the home of Billy Mitchell (Perry Fenwick), where Stevie was knocked out, for clues, but is caught by Billy's wife Honey Mitchell (Emma Barton) and ordered to leave. Once Stevie is discharged from the hospital, the Mitchell family meets in The Queen Victoria public house, with Teddy, Harry, and Barney joining. After receiving pushback, Stevie reveals to everyone that Teddy is his son, and by extension, Billy's half-brother. After everyone's initial shock from the revelation calms down, Teddy slowly builds friendships with Billy and the remainder of the family.

Teddy begins flirting with Sharon Watts (Letitia Dean), to the reluctance of her ex-husband Phil Mitchell (Steve McFadden). After Reiss Colwell (Jonny Freeman) falls into debt with Phil and Sharon, Phil puts together that Reiss is conning him, and furiously threatens him. Teddy calms Phil down before making a deal with Reiss to cover the debt. Following a misunderstanding, Ravi Gulati (Aaron Thiara) endangers Barney by dangling him over the edge of a bridge. As revenge for crossing the family, Teddy and Harry burn down his family's call centre. Still traumatised by the incident, Barney attempts to contact his mother, and Teddy's ex-wife Nicola Mitchell (Laura Doddington). She later arrives in Walford, to Teddy's fury, attempting to reconnect with her sons after spending time in prison. Once Teddy and Sharon attempt to move forward with their relationship, Teddy's frustration with Nicola grows as she makes persistent attempts to sabotage them.

On 6 June 2024, it was first announced that three new characters were to be introduced. Billed as secret relatives of Stevie Mitchell (Alan Ford) and extensions to the soap's Mitchell family, the trio included Teddy, to be played by Roland Manookian, and his two sons Harry (Elijah Holloway) and Barney Mitchell (Lewis Bridgeman). Manookian said that after his audition he didn't believe he would receive the part, and initially ignored calls from his agent as a result. Upon his casting, Manookian expressed his excitement to join the soap, having watched it from a young age. Manookian was also enthusiastic to be cast as a member of the Mitchell family. Describing them as a "stalwart" unit, he added that being a member of the Mitchell family meant he had "big shoes to fill", but he was willing to accept the challenge. Having watched since childhood, he described being on-set as "surreal". The show's executive producer Chris Clenshaw was excited to introduce "a new branch of the iconic Mitchell family" to the show's setting, Walford. Clenshaw also teased that Teddy and his sons would quickly be "thrust into the drama".

Details preceding their arrival said they would arrive in search of Stevie, only to learn that Stevie had another family. Their arrival would cause tension among the Mitchell family, being met with fury from Phil Mitchell (Steve McFadden). It was teased to be a "seismic shock" for Teddy's half-brother Billy Mitchell (Perry Fenwick), as he was unaware of his father's other family, with the arrival to cause "turmoil" for him. Teddy, Harry, and Barney were set to arrive in the show later in June. They made their first appearances in the episode airing on 26 June 2024.

When Teddy's character was announced, Manookian called Teddy an "old school" and "enigmatic" figure, who was nevertheless aware of the contemporary. He concluded that Teddy is a traditional and stoic man, and as a result, he is intelligent enough to adjust. Manookian added that his character was incredibly astute in business and, as a "strong family man", had a deep understanding for his family's needs, as well as how to be there for and protect them. Manookian said he enjoyed playing Teddy as "he's a very strong-willed man" with few weaknesses, but was also charming, humble, and respectful. In Manookian's words: "he's got a very good way with people". Manookian observed that Harry and Barney inherited some of Teddy's characteristics, namely being strategic and tactical. The actor teased Teddy would cause "loads of trouble" for the show's residents, driven by his goal to achieve the greatest possible result for himself. Despite his charm, as a Mitchell, conflict "follows" Teddy. Laura Morgan of What's on TV labeled the character as "cunning". The character moved into Walford as he was "desperate to make a fresh start with his boys". Following his arrival, Teddy's past is left "murky", with Susannah Alexander of Digital Spy noting how the character uses "extravagant gestures" to conceal his secrets. Radio Times writer Laura Denby called Teddy both "charming" and "shifty".

Explaining the backstory between Teddy and his father Stevie, Manookian said the two had a "rocky" relationship, but as Teddy aged, Stevie became progressively "more influential in his life". As their history detailed an on-off amount of contact between the pair, Manookian said there were "renaissances" of their relationship. The actor also detailed that Teddy's respect for Stevie escalated after having his own children, as it allowed him to better understand the sacrifices that came with parenting. Despite this, Teddy was said to have "some repairing to do" regarding his relationship with Stevie. After arriving in Walford and meeting Phil, Manookian said Teddy would be shocked by his aggressive response to his arrival, but would try to stay calm and work things out. Despite this, he considered the characters as being "two bulls locking horns" due to being different types of "alpha male". He explained this as being because Phil is more aggressive and assertive compared to Teddy being just as dangerous, but more strategic and courteous. Discussing Billy's reaction to learning about Teddy, Manookian sympathised with Billy and justified his reaction as being "a hell of a lot to take in".

In October 2024, it was announced that Teddy's ex-wife Nicola Mitchell (Laura Doddington) would be introduced to the soap, with her arrival being teased to be a shock for Teddy. Her introduction followed several ominous mentions in the show. Despite Teddy being reluctant to see her again, due to her arrival breaking the illusion of the family's fresh start, Nicola is determined to stay in Walford regardless. Clenshaw explained that Teddy and Nicola had a "complicated history", which he expressed excitement to explore. Doddington explained their history, including the two meeting while they were young, growing up together and discovering their true selves while dating. As a result, they knew each other very closely and were able to "press each other's buttons" while predicting the outcome. Doddington commented on the present relationship between Teddy and Nicola, explaining that her character wanted to get back together with Teddy, despite admitting that they were a dysfunctional couple and Teddy had since lost interest in her. She added that Nicola would be angry about losing her ability to manipulate and remain two steps ahead of him.

Molly Moss of Radio Times called the character's introduction a "dramatic entrance". Her colleague, Laura Denby, wrote that Teddy's first appearance was a "memorable" and "captivating" debut for the character, expressing interest in seeing more from him. Entertainment Daily writer Joel Harley commented that Teddy had quickly become popular among viewers following his introduction. He displayed positive Twitter reactions praising the character's potential. In August 2024, Rachel Lucas of What's on TV wrote that Teddy had been an "enigma" since his arrival, due to his mysterious past. Denby found Teddy and his initial secrets "intriguing", and wrote that Teddy's revenge against Ravi, by burning down the call centre, was "carefully considered" and "shocking".