Kennedy's first screen role was in
Peter Greenaway's
The Tulse Luper Suitcases, Kennedy's first lead role was playing Richard Carstone in the BBC adaptation of
Charles Dickens'
Bleak House, Kennedy recurred on the television series
Boardwalk Empire in 2012, a lead opposite
Brendan Gleeson in the HBO pilot
The Money, Sampson in ITV's
Downton Abbey, Jock Colville with
Michael Gambon in ''
Churchill's Secret'', directed by
Charles Sturridge, and recurring roles in Hulu's
The First,
Mrs Wilson for the BBC, and Allston Wheatley in
Scott Frank's ''
The Queen's Gambit for Netflix. He appeared in several episodes of The Day of the Jackal'' as the target UDC's partner. Kennedy's other film roles include Lieutenant Waverly in Spielberg's
War Horse, Roger Donaldson's
November Man,
Bill Condon's
Mr Holmes (with
Ian McKellen), Babak Najafi's
London Has Fallen, Lt. Col. Guy L'Estrange in
Mike Leigh's
Peterloo; and as
Edward Aveling opposite
Romola Garai in
Susanna Nicchiarelli's
Miss Marx. Kennedy's stage roles include Lysander in ''
A Midsummer Night's Dream'' at the Bristol Old Vic (directed by David Farr); George Holly in
Michael Grandage's production of
Suddenly Last Summer with
Diana Rigg and
Victoria Hamilton in the West End; the lead role of Jonathan in
Everything is Illuminated at
The Hampstead Theatre; Camille in
Therese Raquin, at the
National Theatre, directed by
Marianne Elliott; Tom in
The Glass Menagerie, for Shared Experience; Oliver in
Polly Stenham's
No Quarter, directed by
Jeremy Herrin at the
Royal Court; and Don Caspar in
Anna Ziegler's
Photograph 51, with
Nicole Kidman, directed by
Michael Grandage at the Noel Coward Theatre. In 2017, Kennedy took the lead roles in
Harold Pinter's
The Lover and
The Collection, directed by
Michael Kahn for the
Shakespeare Theatre Company, Lansburgh Theatre, Washington D.C. Kennedy has worked on several films with the British artist
Nathaniel Mellors, playing the recurring Neanderthal character Voggen Williams in
The Sophisticated Neanderthal Interview,
Neanderthal Container, and the pub lecher, Uncle Tommy, in the
Ourhouse series. In 2018, Kennedy wrote and directed the short film
The Human Voice, starring
Rosamund Pike, adapted from the
Jean Cocteau play
La Voix Humaine. Kennedy portrayed astronaut
Michael Collins in the documentary of the
Apollo 11 mission,
8 Days: To the Moon and Back, shown on
BBC2 on 10 July 2019. ==Filmography==