Has a son named William Douglas Sewell (Billy), born 18 March 2002 with Amy Gardner
He was awarded the 1992 London Critics Circle Theatre Award (Drama Theatre Award) for Most Promising Newcomer.
Son of a film animator who died young.
Grew up in Twickenham.
His father, Bill Sewell, an animator, employed an impressionistic approach to Rotoscoping - the technique of tracing over film negatives - in his own film "Half in Love with Fred Astaire" and then in the famous "Lucy in the Sky with Diamonds" sequence in "Yellow Submarine.".
Involved, along with Sherilyn Fenn, Kate Winslet, Miranda Richardson and Paul McGann in the 1998 film project "Johnny Hit and Run Pauline". The film was to be executive produced by Emma Thompson, and written and directed by Fay Efrosini Lellios. The shooting was set to start in June 1998 in New Hampshire. The film was canceled due to financial withdrawal. 
Was in a relationship with actress Alice Eve from 2006 until 2008.
Reprises his role and outstanding performance as Jan in Tom Stoppard's new play "Rock and Roll" on Broadway, New York City until March 2008. [December 2007]
Currently playing the part of Jan in Tom Stoppard's "Rock and Roll" at the Royal Court Theatre in London (until July 15th 2006) [June 2006]
Currently has the starring role in the TV series "Eleventh Hour" on the (US) CBS Network. [September 2008]
Son of BAFTA-nominated Animation Director, Bill Sewell.