Secret Agent Jack Stalwart Series

In 'The Caper of the Crown Jewels,' Jack is summoned to solve the theft of the Crown Jewels from the Tower of London. He is greeted by a Yeoman Warder who explains the stolen items include the Imperial State Crown, Sovereign's Orb, and Scepter with the Star of Africa. Jack identifies the thieves as Ivan the Incredible and Jazz but struggles to figure out how they bypassed advanced security. Despite using his gadgets, Jack resorts to magic, dispels an invisibility enchantment, and narrowly avoids execution before successfully restoring the jewels and earning the Queen's gratitude.