Honestly, those celeb types. What an attention-seeking bunch they are. Some of them can't even resist hogging the limelight even when it's not their moment.
From Benedict Cumberbatch's now legendary infiltration of U2's red carpet moment at the Oscars and Justin Bieber coming between (literally) Russell Brand and Katy Perry to Jack Black managing to upstage Angelina Jolie (no mean feat) and Dustin Hoffman going for the classic 'bunny ears' behind Dame Judi Dench.
Heck, even our very own Queen got in on the act at the Commonwealth Games after HRH hijacked a selfie of two hockey players and thus instantly gave their snap the royal seal of approval.
Here's our round-up of the best celeb-on-celeb photobombs…