Stephen Gallagher (born 13 October 1954) is an English screenwriter and novelist. Gallagher was born in Salford, Greater Manchester and attended Eccles Grammar School, then graduated from the University of Hull with Joint Honours in Drama and English. First worked as a documentaries researcher for Yorkshire Television and then in the Presentation Department of Granada TV, (now ITV Granada).
Gallagher has written novels and television scripts, including for the BBC television series Doctor Who — for which he wrote two serials, Warriors' Gate (1981) and Terminus (1983)—as well as for the series Rosemary & Thyme and Bugs, for two seasons of which he was script consultant along with Brian Clemens. He adapted his own novel Chimera as a 90-minute dramatized audio drama for BBC Radio 4 in 1985, and as a miniseries of the same name that was shown on ITV in 1991. He also directed the miniseries adaptation of Oktober, as well as writing the feature-length episode The Kingdom of Bones for the BBC series Murder Rooms.
He created and wrote a science-based series for ITV, Eleventh Hour, starring Patrick Stewart as a government science investigator and advisor. The programme was rumoured to be ITV's answer to the new series of Doctor Who, but was more in the tradition of the hard-science thriller. Gallagher's series format was acquired for a US television remake by the ' trio of CBS, Jerry Bruckheimer and director Danny Cannon. The series aired on CBS and starred Rufus Sewell and Marley Shelton.
Life Line, broadcast in 2007, was a two-part supernatural mystery starring Ray Stevenson, Joanne Whalley and Jemima Rooper. Gallagher was later lead writer and story supervisor on NBC's 13-part series Crusoe, screened in 2008/2009, and contributed two episodes to the US version of Eleventh Hour including Medea, the season finale. In 2009 he served as Co-Executive Producer on Bruckheimer's crime show The Forgotten, starring Christian Slater. Legacy, a two-part story for season 16 of the BBC's Silent Witness, was Best Drama winner in the 2013 European Science TV and New Media Awards. He later wrote episodes of Stan Lee's Lucky Man.
In June 2025 the radio drama An Alternative to Suicide was rebroadcast as part of a Hidden Treasures strand on BBC Radio 4 Extra. Starring Michael Jayston and directed by Martin Jenkins, the Saturday Night Theatre production was considered a lost work after the play's master tapes were erased for re-use. A copy was restored to the archive through the work of non-profit organisation The Radio Circle.
Key to collections: CA=Comparative Anatomy, OOHM= Out of his Mind, PM=Plots & Misadventures