His debut work was the audio play The Rapture for Big Finish Productions in 2002. Numerous further audio plays and prose short stories followed for Big Finish, for their Doctor Who line, spin-offs and other series (Sapphire & Steel and The Tomorrow People).
In 2005, he started working for the BBC, doing miscellaneous writing work for tie-in materials for the new Doctor Who television series. It was announced on 16 July 2007 that he would be one of the writers on the second series of Doctor Who spin-off Torchwood, his television debut.
In 2010, Lidster wrote the content for several tie-in websites relating to the fictional world of the new television series, Sherlock.
That Time I Nearly Destroyed The World Whilst Looking For a Dress in Past Tense (2004)
The Tramp's Story in Repercussions (2004)
Trapped! in Monsters (2004)
The Terror of the Darkness in A Day in the Life (2005)
She Won't Be Home in The History of Christmas (2005)
Curtain Call in Farewells (2006)
Prologue and Forgotten in The Centenarian (2006)
Natalie's Diary in Dalek Empire (2006)
Salva Mea in Snapshots (2007)
Keeping It Real in The Ghosts of Christmas (2007)
Prologue for the BBC's Doctor Who website (2007)
Bernice Summerfield
A Summer Affair in A Life Worth Living (2005)
Dead Mice in Something Changed (2006)
Torchwood
Monster in the Torchwood Yearbook (2008)
Consequences (2009)
Novellas
Bernice Summerfield
On Trial in A Life In Pieces (2004)
Audiobooks
Torchwood
In the Shadows (2009)
Other
From 2005 onwards, he wrote the fictional content for the Doctor Who tie-in websites including the MySpace blog for Martha Jones. In 2007, he edited the Doctor Who short story collection [[Short Trips