The other two followed him. They tugged and heaved at the door, but it wouldn't budge, not even when Hermione tried her Alohomora charm.

"Now what?" said Ron.

"These birds... they can't be here just for decoration," said Hermione.

They watched the birds soaring overhead, glittering — glittering?

"They're not birds!" Harry said suddenly. "They're keys! Winged keys - look carefully. So that must mean..." he looked around the chamber while the other two squinted up at the flock of keys. "... yes — look! Broomsticks! We've got to catch the key to the door!"

"But there are hundreds of them!"

Ron examined the lock on the door.

"We're looking for a big, old-fashioned one — probably silver, like the handle."

They each seized a broomstick and kicked off into the air, soaring into the midst of the cloud of keys. They grabbed and snatched, but the bewitched keys darted and dived so quickly it was almost impossible to catch one.

Not for nothing, though, was Harry the youngest Seeker in a century. He had a knack for spotting things other people didn't. After a minute's weaving about through the whirl of rainbow feathers, he noticed a large silver key that had a bent wing, as if it had already been caught and stuffed roughly into the keyhole.