David Tennant was worried working with Matt Smith on 'Doctor Who' would be a "weird situation".
The 42-year-old actor was concerned his decision to reprise his role as the Tenth Doctor on the BBC One sci-fi show's 50th anniversary episode would "backfire" because Matt replaced him as the titular Time Lord - but he was pleasantly surprised the pair worked together so well.
He said: "I suppose you'd expect me to say we're new best friends and I love him like a brother. But that is sort of how it was. I had a fantastic time and that wouldn't necessarily have been the case.
"I'm coming back onto a show that's effectively somebody else's show and used to be mine and that's potentially quite a weird situation to be in. Going back to something I knew so well and had such fun memories of might have backfired.
"It's a quite rare set of circumstances: Pierce Brosnan and Daniel Craig don't get to play James Bond next to each other. But actually it felt familiar enough that it was like coming home and working with Matt proved to be a real joy."
David admits all of his fears about returning to the show disappeared as soon as he and Matt stepped foot in front of the camera together, and he is confident his fellow actor feels the same.
Speaking to Entertainment Weekly, he added: "I hope I'm speaking for him when I say we really enjoyed bouncing of each other and playing sort of two aspects of the same character. It was everything that I hoped it might be and nothing that I feared it could be."