Douglas "Doug" Carter is a fictional character from the British soap opera Hollyoaks, played by PJ Brennan. He initially appeared in the programme's online spin-off series Hollyoaks: Freshers, before debuting in the main series in the episode airing 13 September 2010. He left on 17 September before returning on 13 January 2011, this time as a regular. He was introduced as part of a new student group. His storylines have included drug dealing, a relationship with Jenny (Daisy Turner) which ended in her murder at the hands of a serial killer, an attempted suicide and entering a gay marriage. Doug has described as someone who "doesn't make the best choices" but has the "best intentions". Doug has been described as a fan favourite and came first in a poll to find viewer's favourite of the new fresher group.
Doug takes fellow students Charlotte, Jamil and Dave Colburn (Elliot James Langridge) to France. Doug kisses both Jem and Leanne and starts dealing drugs for Brendan. He supplies Charlotte with drugs, but she falls from an archway and damages her spine. Doug feels guilty and overdoses on cocaine. While in hospital, Carl, who is against Doug being in Jem's life, orders him to return to America. He does so after Carl admits that he was behind a previous attack on Doug. He later returns to make amends and settles back in. After India Longford (Beth Kingston) is murdered her sister, Texas (Bianca Hendrickse-Spendlove) struggles to deal with India’s upcoming funeral and so begs Doug to get her some drugs. At first, he refuses; however, he soon gets the drugs off Brendan and gives her the drugs. She takes the drugs and then sleeps with Doug, but she soon regrets it. On the day of India's funeral, Texas takes more drugs and although Doug tries to help her, she was consequently unable to attend India's funeral. Brendan forces Doug to frame Rae Wilson(Alice Barlow) for cocaine dealing. Riley takes Doug to a party. Riley gets drunk and drives and is pulled over by Ethan Scott (Craig Vye). Before Ethan can see who is driving, Doug and Riley switch places so Riley's career isn't damaged.
Doug bumps into Jenny, whom he knows as "Bex", and it is revealed he was once in a relationship with her. They decide to leave together and scam Brendan and Warren. The plan fails and Jenny arranges a date with Silas, who she intends to drug and steal from. He realises what she is going to do and drugs her before murdering her. Doug is distraught and accuses Brendan of murdering her but he is not charged. Doug and Riley meet Ruby Button (Anna Shaffer) who lies about her identity. Doug takes Ruby to go back to the flat where they kiss, she gets drunk. Doug discovers Ruby's age and takes her home. Seth confides in Doug about his father's affair with Mercedes, behind Riley's back. Warren gets Doug to tell him of the affair and threatens him to keep quiet. Riley is later angry with Doug for keeping the secret. When Silas murders Rae, Brendan is arrested and Doug blames Cheryl Brady (Bronagh Waugh) for giving him an alibi at the time of Jenny's murder. Lynsey tells Doug that Silas is going to murder again on Halloween and he believes her. He helps her to try and figure who is next victim shall be. However, they fail to stop him from killing again - but he unintentionally kills his daughter, Heidi Costello (Kim Tiddy).
Doug goes on a date with Jodie, but she rejects his advances and tells him he is not over Jenny. Doug faces Christmas alone when Texas and Leanne go to spend it with their families. Doug prepares a meal for one and drinking alcohol. He then goes out and climbs onto a bridge, looks at a photograph of Jenny and throws himself into the river. While unconscious he has visions of Steph; she shows him how he has changed the lives of his friends. He then has visions of Jenny and has to choose whether or not to live. Paramedics revive Doug and he decides to move on with his life. Doug and Ste Hay (Kieron Richardson) decide to start a business together. Their first venture fails, so they attempt to get a loan to buy Cincerity and open a deli. They are refused a loan and Doug secretly borrows the money off Brendan. Doug and Ste spend more time together, when Ste hugs Doug he becomes confused. Doug helps Ste set up a dating profile and starts acting different around him. Leanne accuses Doug of being jealous of Ste and he becomes uncomfortable when Leanne makes them perform a flirtation role play. Ste has a date with Adam (Alex Morgan) and Doug becomes jealous. He sleeps with Texas and they blame it on too much alcohol. Doug ruins Ste's date with Adam and during an argument Doug insinuates that he loves Ste and Adam later dumps Ste. Doug confesses his feelings to Ste and they kiss and later start a relationship but Ste later dumps him after Doug reveals he borrowed £80,000 from Brendan. Ste plays Brendan in order for him to clear the debt and then returns to Doug, restarting their relationship.
Doug and Ste become engaged. In the lead up to their wedding, Doug become paranoid about Brendan's involvement in their relationship. Walker (Neil Newbon), an undercover police officer, convinces Doug to help him find evidence on Brendan. Doug agrees but Walker plans to get Doug out of his way so he can kill Ste as to take revenge on Brendan. Walker plans to shoot Ste but in a scuffle he shoots a stray bullet which hits Riley, killing him. Doug later becomes paranoid about Brendan still loving Ste so contacts Walker's boss Shawnee (Josie Taylor), telling her he can help get evidence on Brendan. Doug fails at first, but tricks Brendan so he admits that he killed Danny Houston (Darren Day) to protect Ste on a recording. Doug and Ste marry. At their wedding reception, Ste finds the recording and declares the marriage over. Ste is run over by Maddie Morrison (Scarlett Bowman) after saving his adoptive daughterLeah Barnes (Ela-May Demircan). The minibus then crashes in to the wedding venue.