[6] From November 2015 to February 2016 he played Max in The Homecoming at Trafalgar Studios,[3] and later appeared at the Donmar Warehouse as Teddy in Brian Friel's Faith Healer in 2016.
[7][8] From November 2016 to January 2017, Cook appeared in Lucy Kirkwood's new play The Children at The Royal Court Theatre with Francesca Annis and Deborah Findlay.
[3] He has performed in a large number of television productions, including guest roles in episodes of series such as The Black Adder[3] where he played "Sean the Irish bastard" (1983), and Bergerac (1988),[3] Sharpe (1994) [3] and Doctor Who, "The Idiot's Lantern" (2006).
[3] He appeared as one of the unnamed "mysterious men" haunting the imagination of Michael Gambon's hospitalised writer in Dennis Potter's acclaimed 1986 serial The Singing Detective,[3] Jack Rosenthal British television play Day To Remember[3] and has featured in several costume dramas, including Stephen Poliakoff's The Lost Prince (2002 as David Lloyd George),[3] an adaptation of The Hound of the Baskervilles (2002, as Barrymore), a TV adaptation of The Other Boleyn Girl,[3] (2003 as Thomas Cromwell), Anthony Trollope's adaptation He Knew He Was Right (2004, as Bozzel), and Russell T. Davies's Casanova (2005, as the prisoner in the cell next to Casanova's).
[3] Other film roles have included parts in The Cook, the Thief, His Wife & Her Lover (1989, as Mews), Secrets & Lies (1996),[3] The Odyssey (1997, as Eurybates), Topsy-Turvy (1999, as Richard D'Oyly Carte), Chocolat (2000), Charlotte Gray (2001), 24 Hour Party People (2002, as Derek Ryder), Thunderbirds (2004, as Parker), 102 Dalmatians, Hot Fuzz (2007, as George Merchant)[3] and The King's Man (2021, as Archduke Franz Ferdinand).
[3] Cook also appeared in Feeling Good, a short film written by Dexter Fletcher and directed by Dalia Ibelhauptaite.
In July 2007, he played the part of Kris Kelvin, the protagonist psychologist on the BBC Radio 4 adaptation of Solaris, Stanislaw Lem's novel.