Dev Alahan is a fictional character from the British ITV soap opera Coronation Street. Portrayed by Jimmi Harkishin, the character's first appearance was broadcast on 10 November 1999. He is the ex-husband of Sunita Alahan (Shobna Gulati), husband to Bernie Winter (Jane Hazlegrove) and father to Amber Kalirai (Nikki Patel), Aadi Alahan (Zennon Ditchett/Adam Hussain) and Asha Alahan (Tanisha Gorey). It is suggested that Alahan has fathered children other than these, with one of them named Shareen. Harkishin took breaks from the role on several occasions including in 2004, 2015, 2019 and 2025.

In December 2004, it was announced that Harkishin had decided to take a break from Coronation Street following revelations about his private life. A spokesperson for Granada said Harkishin had been granted indefinite leave to sort out his "problems" and had their full support. A decade later, Harkishin asked for an extended break from the soap, departing on 13 February 2015 and returning on 1 June of that year. On 6 April 2019, it was announced that Harkishin would take a two-month break. In February 2025, it was announced that Harkishin would be taking another temporary break from the soap in order to go travelling for his 25th year on the soap. In the storyline, Dev goes to India to be with his family after his aunt Gita has a fall, and his partner Bernie Winter (Jane Hazlegrove) offers to go with him, although it was hinted that she may not.

On 12 February 2001, it was announced that Coronation Street would introduce a new Asian character named Sunita Alahan played by Shobna Gulati. Sunita was given an immediate link to established character Dev as she was an employee at his shop in Swinton. Sunita and Dev later went on to begin a relationship and eventually get married. The marriage ended in 2006 when Sunita was axed from the show.

On 16 May 2009, it was confirmed that Gulati would be returning to the programme, reprising the role of Sunita. Coronation Street producer Kim Crowther first hinted at a possible return for Sunita in an interview with entertainment website Digital Spy the previous week. She said: "We have a great new direction for Dev after Tara [Mandal]'s (Ayesha Dharker) exit. Further down the line, we build more family around Dev again and it might signal the return of some old faces…"

Amy Goskirk (Jayne Ashbourne), an ex-girlfriend, follows Dev to Weatherfield, claiming he had promised to marry her. He denies this, claiming she is mentally unstable so she claims to be pregnant with his baby and that she had attempted suicide. When she turns up at the Rovers Return with bandaged wrists, Dev exposes her lies by ripping off the bandages, revealing no cuts.

Some time later, Dev almost marries barmaid Geena Gregory (Jennifer James), but her mother is unhappy and pays Karen McDonald (Suranne Jones) to set him up so Geena will dump him. Although she forgives him, Geena and Dev later split up and she starts dating Joe Carter (Jonathan Wrather). Dev saves shop assistant Sunita Parekh (Shobna Gulati) from an arranged marriage, giving her a safe haven in the flat above the Corner Shop. Sunita develops feelings for Dev but he initially sees her as just a friend, but they later get involved. His other girlfriends include: cruise ship hairdresser Debs Brownlow (Gabrielle Glaister), and Tracy Preston (Kate Ford), who wrecks his flat after discovering he has no intention of marrying her. He also sleeps with Tracy's mother, Deirdre Rachid (Anne Kirkbride), who he later employs.

Dev later meets solicitor Maya Sharma (Sasha Behar), while on the rebound from Sunita, who chooses barman Ciaran McCarthy (Keith Duffy) over him. He allows Maya to move in and she makes friends with Frankie Baldwin (Debra Stephenson), but gets jealous of the amount of time Dev and Sunita are spending together and forces him to choose. As Sunita is seriously ill, he chooses her. This enrages Maya so she smashes up his flat and frames Sunita for an illegal immigration scam so she is arrested on her and Dev's wedding day. Sunita is jailed but released when one of the illegal immigrants Maya married is arrested for a completely separate offence and identifies Maya as his "wife", pleading with her for help in front of the police. Maya is charged but released on bail and wanting revenge, she ties up Sunita and sets fire to all of Dev's shops, knocking him unconscious when he tries to rescue Sunita and leaves them to die. However, Ciaran and Charlie Stubbs (Bill Ward) save them.

Dev's marriage to Sunita is happy for a while, and the couple is overjoyed to discover that Sunita is expecting twins. Dev then sells his share of Streetcars to Lloyd Mullaney (Craig Charles) in order to buy a house for his new family. However, during 2005, Sunita takes in teenage Amber Kalirai (Nikki Patel), daughter of one of his employees as her mother is in hospital. Dev is unhappy at Amber's presence and Sunita is shocked to learn that Dev is her biological father, due to a brief relationship years ago. However, Sunita then learns that Dev has other children by women he employs and grandchildren too. Sunita is devastated, especially when Dev admits having very little contact with his daughters, and leaves him. She allows him to be present when she gives birth to the twins, who are named Asha and Aadi. Dev is overjoyed (especially as Aadi is his first son), but Sunita cannot forgive him so she leaves the street with the twins, moving into the house that Dev had bought. Dev, however, is allowed to have regular contact with the twins.