Doctor Who: 20 Things You Didn't Know About Blink
11. Young Billy And Old Billy Were Almost Played By The Same Actor
Even though he only appeared in a handful of scenes, Billy Shipton left a memorable mark on Doctor Who.
After showing Sally the Wester Drumlins collection (and asking her out), Billy is sent back in time by the Angels, and ends up playing a key role in getting the Doctor's information to Sally in the future.
We see Billy in two different forms: one where he's young, and one where he's old. The original plan was to make actor Michael Obiora look older to play his aged self, until Russell T Davies stepped in.
Davies (along with producer Phil Collinson) felt that audiences would find it harder to invest in old Billy's plight if they could see he was played by an actor in makeup. Everyone agreed, and so veteran performer Louis Mahoney was brought in as old Billy.
Interestingly, Obiora and Mahoney played father and son in the BBC drama series Sea of Souls, which was also produced by Phil Collinson. Small world!