After an episode of The IT Crowd is criticised as transphobic, Linehan becomes involved in anti-transgender activism. He argues that transgender activism endangers women, and likens the use of puberty blockers to Nazi eugenics. He says his views have lost him work and ended his marriage.
Linehan attends Catholic University School, a Roman Catholic secondary school for boys. In the 1980s, he joins the staff of the Dublin politics and music magazine Hot Press, where he meets his future writing partner, Arthur Mathews. In their early collaborations, they create segments in sketch shows including Alas Smith and Jones, Harry Enfield & Chums, The All New Alexei Sayle Show, The Day Today and the Ted and Ralph characters in The Fast Show. They continue their collaboration with Paris (one series, 1994), Father Ted (three series, 1995–1998), and the first series of the sketch show Big Train. They also write the “Dearth of a Salesman” episode for the series Coogan’s Run, which features the character Gareth Cheeseman. In late 2003, he and Mathews are named one of the 50 funniest acts to work in television by The Observer. Father Ted wins BAFTA awards for Best Comedy in 1996 and 1999.
Linehan writes for the satirical series Brass Eye (1997), Blue Jam (1997–1999) and Jam (2000). With the actor Dylan Moran, he creates the sitcom Black Books (2000–2004). He writes and directs the 2006 Channel 4 sitcom The IT Crowd, in which he seeks to move away from the British trend towards mockumentary comedies. Unlike many series of the time, it is recorded before a studio audience. In November 2008, he is awarded an International Emmy for The IT Crowd. In 2013, he writes and directs the sitcom The Walshes. He co-writes the first series of the BBC sitcom Motherland and directs its pilot episode. In 2014, he wins his fifth BAFTA, for Best Writer, Comedy, for his work on The IT Crowd. He is also nominated for Count Arthur Strong.
In 2018, Linehan and Mathews announce plans for a Father Ted musical. Lineham says it will finish the series as they had planned it before the death of the lead actor, Dermot Morgan. The musical is cancelled by producers following the controversy over Linehan’s views on transgender rights. In December 2024, he announces plans to move to Arizona to work on a sitcom and create a production company with the comedians Rob Schneider and Andrew Doyle.
Hannon is founder and mainstay of The Divine Comedy, a band which achieves their biggest commercial success in the last half of the 1990s with the albums Casanova (1996), A Short Album About Love (1997), and Fin de Siècle (1998). He continues to release albums under The Divine Comedy name, the most recent being Office Politics (2019). In 2000 he and Joby Talbot contribute four tracks for Ute Lemper‘s collaboration album, Punishing Kiss.
In 2006 it is announced that Hannon is to lend his vocal ability to the Doctor Who soundtrack CD release, recording two songs – “Love Don’t Roam” for the 2006 Christmas special, “The Runaway Bride“, and a new version of “Song For Ten”, originally used in 2005’s “The Christmas Invasion.” On January 12, 2007, The Guardian website’s “Media Monkey” diary column reports that Doctor Who fans from the discussion forum on the fan website Outpost Gallifrey are attempting to organise mass downloads of the Hannon-sung “Love Don’t Roam,” which is available as a single release on the UKiTunes Store. This is in order to attempt to exploit the new UK Singles Chart download rules, and get the song featured in the Top 40 releases.
The same year Hannon adds his writing and vocal talents to the Air album Pocket Symphony, released in the United States on March 6, 2007. He is featured on the track “Somewhere Between Waking and Sleeping,” for which he writes the lyrics. This song had been originally written for and sung by Charlotte Gainsbourg on her album, 5:55. Though it is not included in its 2006 European release, it is added as a bonus track for its American release on April 24, 2007.
Hannon is credited with composing the theme music for the sitcoms Father Ted and The IT Crowd, the former theme composed for the show and later reworked into “Songs of Love,” a track on The Divine Comedy’s breakthrough album Casanova. Both shows are created or co-created by Graham Linehan. A new Divine Comedy album, Bang Goes the Knighthood, is released in May 2010.
Hannon has collaborated with Thomas Walsh, from the Irish band Pugwash, to create a cricket-themed pop album under the name The Duckworth Lewis Method. The first single, “The Age of Revolution,” is released in June 2009, and a full-length album is released the following week. The group’s second album, Sticky Wickets, comes out in 2013.
In April 2012 Hannon’s first opera commission, Sevastopol, is performed by the Royal Opera House. It is part of a program called OperaShots, which invites musicians not typically working within the opera medium to create an opera. Sevastopol is based upon Leo Tolstoy‘s Sevastopol Sketches. Hannon’s second opera for which he writes music, In May, premiers in May 2013 in Lancaster and is shown in 2014 with overwhelming success.
The world premiere of “To Our Fathers in Distress,” a piece for organ, is performed on March 22, 2014, in London, at the Royal Festival Hall. It is inspired by Hannon’s father, Rt. Revz. Brian Hannon, who suffers from Alzheimer’s disease.
Hannon’s partner is Irish musician Cathy Davey. The couple live in the Dublin area. He is previously married to Orla Little, with whom he has a daughter, Willow Hannon. With Davey, Hannon is a patron of the Irish animal charity My Lovely Horse Rescue, named after the Father TedEurovision song for which he wrote the music.
Politically, Hannon describes himself as being “a thoroughly leftie, Guardian-reading chap, but of the champagne socialist variety.”