Whose behind?Take a moment to test yourself.

Let your eyes wander over the rear view of this star.

Can you possibly guess whose face is on the front side?

It may be harder than you think.

We feel it's our duty to give you some hardcore training in celeb spotting.

Our new game should prepare you to spy a star even from the back.

... After all, we'd hate for you to miss out on a top spot for lack of celeb knowledge.

So get your thinking caps on and work out this A-lister - but she's just for starters.

We've popped together an array of stars - all with a photographer behind them.

Will you be top of the class or will you need some extra swotting?

Crack on and see how well you do in identifying them in our gallery below.