Matt Smith has revealed that A Christmas Carol guest star Sir Michael Gambon is the reason he started to wear brightly coloured socks.

“I saw him at the National Theatre, where I was doing a play at the same time, and he’d be in the cafe upstairs drinking tea wearing these mad coloured socks,” the Eleventh Doctor explained in an interview with Digital Spy. ”I always thought they looked cool, so then I started wearing them, and I told him at the read-through!”

Aside from his impeccable taste in footwear, Matt was also impressed by Gambon’s attitude on set. “He’s just brilliant,” he praised. “He just doesn’t disappoint, as a human and as an actor. He’s everything you want Michael Gambon to be. Cool, cool guy.”

A Christmas Carol will air on Christmas Day at 6pm on BBC One/BBC One HD.