Gordon Seed
From Tardis Wiki, the free Doctor Who reference
Gordon Seed is a stunt performer on the BBC Wales version of Doctor Who, whose body type has allowed him to emulate David Tennant, Arthur Darvill, and Matt Smith. He was used with particular frequency during series 5. Although credited as early as The Idiot's Lantern, much of his work has gone uncredited. However, he was regularly seen — if not interviewed — during the fifth series of Doctor Who Confidential, particularly on the episodes that accompanied Amy's Choice and Vincent and the Doctor.
For the series 6 episode The Girl Who Waited, he was assistant stunt co-ordinator.
