Smith, who currently plays the Eleventh Doctor, explained that he loves the peculiarity that Troughton brought to the role.
"I love Patrick Troughton. [Troughton's 1967 serial] 'Tomb of the Cybermen' is one of my favourite stories. It's so creepy," he told Newsarama. "What I think is wonderful about Troughton is he's weird and peculiar but he never asks you to find him weird and peculiar. He was a great actor. And I think the Cybermen are as scary as they've ever been in that one story."
Troughton portrayed the renegade Time Lord from 1966 to 1969, facing Cybermen on a moon base and Yetis in the London underground along the way.
Watch Patrick Troughton's Doctor Who regeneration below:
Smith recently revealed that he would love to film a multi-Doctor episode in honour of Doctor Who's 50th anniversary in 2013.
Doctor Who returns to BBC America in the US on August 27 and will likely air on the same day on BBC One in the UK.
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Watch a trailer for Doctor Who below: