So what would you do if you were introduced to Jude Law and promptly fell off your chair? Personally, we'd either run from the room crying - or carry on as if nothing had happened.

However, as you can see from this video, when reporter Poppy Jamie took a tumble at a press junket for Anna Karenina, she dissolved into helpless giggles. And then Jude started laughing, too. And later on, even Keira Knightley joined in the chuckles. What japes!

Still, you'll be pleased to see that both Jude and Keira had recovered their composure in time for the film's London premiere on Tuesday...

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