Simon Pegg and Nick Frost didn't realise they were working on a new film together until they read about it in a magazine.
The pals - who have starred in The World's End, Hot Fuzz and Shaun Of The Dead together - had no idea they were both voicing characters in the animated film Box Trolls.
Nick explained why they hadn't known about each other's involvement, saying: "When you shoot you're never in the same place at the same time."
Simon went on: "I read it in the trades (trade magazines), oh Nick's in that too, because I play the father of one of the characters and Nick plays one of the box trolls so we're not a double act in it."
But Simon assured fans his collaborations with Nick weren't over yet.
He said: "We've got two more Tintin films to do so that's definite and we've got ideas for films we want to make together. Me, Nick and Edgar [Wright, director of the duo's films] will work together again. It's totally in our plans to keep going, it's just that this series of films that involves guys trying hard not to grow up or trying to grow up, about conformity and featuring ice cream is finished now."
Nick added: "Good ideas don't diminish with time. Often we have an idea to do something which wouldn't work until we're over 50."
The World's End is released in cinemas now.