Christian is first mentioned when his older sister Jane Beale receives an invitation to his civil ceremony with partner Ashley Jennings. Jane throws the invitation away but it is later found by Jane's husband Ian Beale. Jane refuses to tell Ian why she does not want to go to the ceremony but Ian wants to meet Christian, and invites him and Ashley to dinner at Fargo's Restaurant. Christian reveals that he was once in love with Jane's first husband David Collins. Ashley storms out of the restaurant and the couple end their relationship. Christian arrives in Walford as he has nowhere to stay. He apologises and Ian allows him to move in. Christian flirts with Ian's stepson, Steven Beale, so Steven pretends Stacey Branning is his girlfriend to put Christian off. Roxy Mitchell tries to chat him up, but is shocked to discover a stripper he had hired for his sister was an ex-boyfriend of his. They go on to become close friends. He becomes involved in a love triangle between Steven and Stacey, as Steven begins to experience confusion over his sexuality. He and Steven share a kiss but Steven falsely claims that Christian made a move on him; as a result, Christian leaves the Square. He returns after Steven's lie is exposed. Christian is tricked by Ian's daughter Lucy Beale into letting her use his flat so she can spend some "quality time" with her boyfriend, Olly Greenwood. Christian walks in on them about to have sex and stops them. Ian punches Christian over what happened with Lucy and Olly, but when he catches Lucy attempting to leave with Olly, he insists she move in with Christian again.
Christian is surprised to see his mother Linda Carter after having lost contact with her for nearly 20 years. At first, Christian dislikes her because she still disapproves of his sexuality, but when Ian's son Peter Beale tells him how he lost his mother Cindy Beale, Christian makes amends with her. Roxy unexpectedly goes into premature labour, and Christian offers to help raise the baby, Amy, as her marriage to Sean Slater has ended. However, Roxy leaves Christian heartbroken when she gets back with Sean. She later tells Christian that he is to be Amy's godfather. Roxy gives her daughter the middle name Christina, after Christian. Christian's colleague at Masala Queen, Syed Masood, argues with him over his sexuality, saying that homosexuality goes against his God's will, but then unexpectedly kisses and has sex with Christian. Syed tries to avoid Christian, although Christian wants to begin a relationship with him. Syed refuses him although they continue with their affair, Syed eventually denies that he is gay and proposes to his girlfriend Amira Shah. On the day of Syed and Amira's engagement party, Christian takes a man called Luke back to his flat, but Luke beats Christian up after revealing he is not gay and hates gay men cottaging in public places. Following this, Christian becomes agoraphobic, but Syed helps Christian return to a normal life. Christian's friend James Mackie turns up, and Syed sees them together and is jealous. After James admits that he has feelings for Christian, Syed tries to put him off. Christian finds out and tells Syed that he will be with him but he must break up with Amira, but Syed cannot go through with it, so Christian starts a relationship with James. However, one day Christian takes Syed down an alleyway and kisses him, not realising they have been seen. Christian then breaks off his romance with James and restarts his secret affair with Syed. Christian and Syed are photographed looking cosy in an alleyway. Syed is blackmailed and Christian discovers it is Lucy. Syed soon breaks off the affair, and Christian tells Syed he cannot help arrange his wedding any more.
On the wedding day, Syed admits to Christian that he is gay but cannot come out because he is not just gay, but a son, a brother and a Muslim. When he runs away, distressed, Syed's mother Zainab Khan sees and confronts Christian who tells her everything, but she does not believe him and attacks him verbally and physically. She then goes to the wedding and confronts Syed who eventually confesses, and she tells him to marry Amira. When Syed and Amira return from their honeymoon, Christian introduces a man called Leyton as his boyfriend to make Syed jealous, which works as Syed is clearly upset. However, after Syed and Amira consummate their marriage, Syed tells Christian that they are planning a baby, and says he and Christian can both move on as Christian has Leyton and Syed has Amira. However, Christian tells Syed he has broken up with Leyton and was only with him to make Syed jealous. At Syed's and Amira's flat, Christian and Syed argue, but are then seen kissing on floor of the flat by Syed's father, Masood Ahmed. This leads to the exposure of their affair, and Syed comes out to his family and friends, and Amira leaves Walford. However Syed rejects Christian again. Amira's father Qadim Shah and his associates track down Christian, wanting to know where Syed is. Christian says he does not know, so they beat him and leave him outside on the pavement. When Syed returns, he apologises to Christian but Christian calls him a coward, saying he never wants to see him again. Syed has therapy to attempt to cure his same-sex attraction, and he tells Christian he no longer feels anything for him. However, Syed soon admits to Christian that his therapy has not worked and he wants to admit his true feelings. Christian pushes him away, but the next day he accepts Syed when he says he chooses Christian and turns his back on his family. The pair then move in with each other. On New Year's Eve, Christian attends a party at The Queen Victoria pub, and shares a kiss with a man. Christian tells Syed, and Syed is angry, but later forgives him. They decide they would like a child and a drunken Roxy offers to be the surrogate mother. However, despite their attempt, she does not become pregnant. Syed and Christian decide to adopt, and Christian later proposes to Syed, and Syed agrees. They continue with their plans to adopt and Christian finds a new flat for them. However, Syed almost changes his mind and the couple split up until Syed realises that he does want children.
Christian starts working at the local boxing club, and whilst there, 15-year-old Ben Mitchell confides to him that he is gay. Christian gives advice to the teenager, but Ben develops a crush on Christian, which he discourages. Amira returns to Walford with hers and Syed's baby, Yasmin. She promptly tells Syed that she wants him to be a part of their baby's life but bans Christian from seeing her. Syed starts to secretly see Amira and Yasmin, and Ben reports this to Christian. Christian confronts Syed and declares that Syed has to choose between him and the baby. However, he relents and gives Syed his blessing to see his child. However, Yusef Khan suggests to Christian that Yasmin may not be Syed's child, casting doubt in Christian's mind. Christian then asks Yusef to perform a secret paternity test on Yasmin. The results of the test state that Syed is not the father of Yasmin, and Christian reveals this to Syed and Amira. Syed is devastated, but Amira continues to claim that he is the father. Syed doubts Christian, believing that he may have falsified the test. However, it emerges that it was Yusef who falsified the paternity test. Christian feels hurt that Syed suspected him of lying, but he reluctantly agrees to let Amira and Yasmin stay with him and Syed as they have nowhere else to go. Christian is annoyed to discover that Syed is helping Amira get a home in Walford. When Christian and Ben watch a film together, they talk about Christian and Syed's relationship and Ben misreads the signals, and tries to kiss Christian. Christian is horrified and Ben runs out of the flat, seen by Zainab and Yusef. Ben later lies to Yusef that Christian touched him inappropriately, and Yusef takes Ben to tell his father, Phil Mitchell. Phil confronts Christian in the pub, and Christian punches Phil when he calls him a "nonce". Phil leaves but later turns up at Christian's flat, smashing it up and hitting Christian with a baseball bat. Ben is forced to tell the truth so Phil leaves. However, Christian is upset with Syed for not trusting him, and when Amira tells Christian that he will be judged by the community, Christian decides to break up with Syed and leave Walford. Christian returns to Albert Square to spend Christmas with Jane. When he sees Syed and Amira, he mocks them for behaving like a couple. Syed is determined to win Christian back and asks Amira for a divorce. Christian and Syed reunite, but Amira vows to stay around. Amira later teases Christian that he will never be invited to Masood family occasions, and he tells her that her business with Syed is a smokescreen and she really wants him back. However, Amira soon tires of Walford without a husband, and leaves her daughter Yasmin in the care of Syed and Christian.
During a Masood family crisis, Christian is asked to look after Zainab on her own, and they talk. She tells him about how she lied to Yusef so that he would be killed (Zainab told him that his daughter Afia Masood was trapped in a burning building). She wonders who will forgive her, and Christian tells her that he does. He explains that they never chose to be the people they are, and she asks if he loves Syed. He says that he does and she realises that when he said it before, she never really listened. They make amends and Zainab invites Christian to a family dinner and to the mosque. When Christian decides to enter Yasmin into a "beautiful baby" competition, Syed is angry, and refers to Yasmin as his daughter, not his and Christian's, leading to an argument between them. Before their wedding, Syed reveals to Christian that he kissed Danny Pennant, but Christian says it was just a kiss and they marry. However, Syed is in debt to Danny, who texts him. Christian sees the texts and meets Danny, who reveals that he had sex with Syed. Christian punches Danny and Syed then finds Christian badly beaten. Christian lies that he was the victim of a homophobic attack, and refuses to give Syed any details. Syed calls the police to report the assault. However, Christian is arrested for the assault on Danny. Danny tells Syed he will only retract his police statement if Syed returns £500 he owes. However, Masood threatens to tell the police about Danny's dodgy investments, so Danny withdraws the allegations. Christian asks Syed for his reassurance of their love and marriage or he will end their relationship. Syed cannot give it, so Christian moves out. Amira returns, wanting to take Yasmin to live with her and her new fiancé in Birmingham. Syed allows Amira to take her, not telling Christian, who is angry when he finds out. He plans to move to America to live with Jane. Syed discovers this through Masood, and brands Christian a hypocrite. Zainab and Lucy lock the pair in the Masoods' restaurant where they reunite. Refusing to leave without Syed, Christian has Jane book them both tickets and they leave together to go to America, planning to live closer to Amira and Yasmin once they return to the UK.
In May 2014, Ian visits Christian at his home in Birmingham following Lucy's death, where Jane is also staying. Christian comforts Ian and expresses his condolences. Ian asks after his son Bobby Beale, who is also staying with them and meets Yasmin, who Christian is babysitting whilst Syed is at work. Christian promises to attend the funeral and after Ian has left, Jane returns home and tells Christian that she won't be attending the funeral. Christian is disappointed by her behaviour. The following day, Christian returns to Walford with Bobby to attend the funeral, travelling in the family car to the church with Ian, Peter and Bobby. Following the service, Christian catches up with Roxy and asks after Amy. He then returns to Birmingham with Jane and Bobby. In February 2015, Christian returns for Jane's wedding. He calls Jane pretending that he has to work, but he arrives in the salon where Jane is getting ready moments later to surprise her.
In May 2016, Christian returns after Jane is attacked by Bobby with a hockey stick. While Jane is comatose, Ian tells Christian that Bobby killed Lucy and Jane covered it up. Christian is shocked when he finds out that Steven has returned and he doubts his intentions. The next day, Linda reveals that Christian has gone back to Birmingham.