Winner and nominee of over 15 awards for his produced work, he has written on several major television series, such as Devils, Collision, The Swarm, and Young Wallander.

He went on to write and direct several shorts, with his short film Does God Play Football[2] starring Kevin McKidd and Helen McCrory winning the crystal Bear at Berlinale Film Festival 2005 and went on to win or be nominated for a further nine awards.

[4] In 2019, he wrote and executive produced on Devils, a Sky Italia banking thriller series, starring Patrick Dempsey, based on the novel by Guido Maria Brera.

[6] On 23 November 2020 it was announced that Legendary Entertainment and Watford & Essex are developing a new version of Voyage to The Bottom Of The Sea with Walker and Chris Lunt writing the project.

[8] Premiering at the Berlinale Film Festival 2023, The Swarm went on to win Best Series at the German Television Awards.