Policeman (An Unearthly Child)
From Tardis Wiki, the free Doctor Who reference
The Policeman was patrolling the Coal Hill area carrying a torch and was seen on Totter's Lane on a foggy night or pre-dawn morning. As he passed the junkyard, he shined his torch on it's wooden gate, which read "IM Foreman - Scrap Merchant - Totters Lane". He paused for a moment, then quickly moved on to finish his patrol. He didn't notice the odd humming sound coming from inside. (DW: The Pilot Episode, An Unearthly Child).
Behind the Scenes
For a reason unknown, the actor playing the Policeman was changed after the Pilot Episode from Fred Rawlings to Reg Cranfield, who played him in the broadcasted An Unearthly Child.