Locker 213

When Iris pries open a school locker sealed shut for decades, she finds a trail of ciphers and clues to a mystery everyone forgot. Can she follow the puzzles to the truth?

Iris Okafor noticed the locker on the very first day she stayed late for the homework club. While everyone else clattered down the hall toward the buses, she lingered by the dim back corner of the third floor, where the lockers were painted an old, chipped green nobody bothered to fix.

Most of them stood half-open and empty. But one was different. Locker 213 had a heavy padlock crusted with rust, and a strip of yellowed tape across the door with two faded words: DO NOT OPEN.

'Forty years that thing has been shut,' said Mr. Bassocio, the janitor, rolling his mop bucket past. 'Older than me, even. Nobody has the key. Honestly, kid, I think everybody just forgot about it.'

Iris could not stop staring. A locked door that nobody had opened in decades felt less like junk and more like a secret waiting for someone to be curious enough.