He joined Bolt Thrower on 21 August 1997. He played drums on Mercenary and the Into The Killing Zone tour, then left the band in 2000 due to lack of interest in the musical direction that Bolt Thrower were taking.
He has also played with Badly Drawn Boy, Groop Dogdrill, New Young Pony Club, UNKLE, Saint Etienne, Bat For Lashes, played guitar with Fridge and under the name Earl Shilton, he has released the album Two Rooms (Full of Insects) released on the Invisible Spies record label.
On 29 May 2008 Natasha Khan announced the new Bat For Lashes live line-up in advance of her support slot on the Radiohead 2008 European tour. "The Blue Dreams" includes Thomas.
As of 2018 Alex has been playing with Anna Calvi appearing on her album "Hunter". On 2 September 2019 Alex was welcomed in to the Zildjan Family of worldwide Artists.
- Bolt Thrower - Mercenary (1998)
- Earl Shilton - Two Rooms Full of Insects (2003)
- Badly Drawn Boy - One Plus One Is One (2004)
- Adem - Love and Other Planets (2006)
- Badly Drawn Boy - Born in the UK (2006)
- Supreme Vagabond Craftsman - Just You, Me and the Baby (2006)
- Bat For Lashes - Two Suns (2009)
- Philip Selway - Running Blind EP (2011)
- Air - Le Voyage Dans La Lune (2012)
- John Cale – M:FANS (2016)
- Bloc Party - Hymns (2016)
- Anna Calvi - Hunter (2018)