Gangsta Granny by David Walliams is a humorous and heartwarming children's novel about Ben, an ordinary boy, and his seemingly dull grandmother, whom he is forced to visit every Friday. He initially finds her boring, but everything changes when he discovers her secret: Granny used to be an international jewel thief! Together, they embark on an adventurous plan to pull off the biggest heist in history—stealing the Crown Jewels.

The story explores family relationships, the power of imagination, and the unexpected excitement hidden in the ordinary. It’s filled with Walliams' signature humor and illustrations by Tony Ross, making it engaging for young readers.