When a powerful experimental bomb is stolen from a secure British facility, Prime Minister Benjamin Disraeli assigns intelligence chief Sidney Orebar to recover it. Working with his top agents, Moira Hunter and Liza Hart, Orebar traces the stolen weapon through the London docks and a rail yard, uncovering that it has been dismantled and moved in parts. The trail leads to an abandoned factory, where a rogue mastermind has reassembled the bomb and plans to unleash it. In a final confrontation, the team fights to stop him, and Moira manages to disable the device just in time, saving the city from destruction.