Marcus has just started Merlin's, a very unusual school...

He doesn't like it and is doing everything he can to get into big trouble and be sent home. When a midnight prank accidentally wakes a sleeping giant called Crom, things take a turn for the magical.

But there are other giants on the move, bigger and angrier than Crom. Realising that Merlin's and the whole country are in danger, it's a race against time for the two new friends to find the magic of their own bravery.