Sixteen-year-old Clary Fray is an ordinary teenager, who likes hanging out in Brooklyn with her friends.

But everything changes the night she witnesses a murder, committed by a group of teens armed with medieval weaponry.

The murderous group are Shadowhunters, secret warriors dedicated to driving demons out of this dimension and back into their own.

Drawn inexorably into a terrifying world, Clary slowly begins to learn the truth about her family - and the battle for the fate of the world.