In London, a boy named Philip lives with his wealthy family and collects pets, encouraged by his grandfather, a famous hunter. When his mother travels to Rome, Philip stays with his grandfather, the maid, and the chauffeur. However, the maid and chauffeur plot to kidnap Philip, but their plan fails when he visits a pet shop and receives a black mamba instead of a harmless snake. The mamba's owner, Dr. Stowe, discovers the mistake and calls the police, who surround the house, led by Commander Bulloch. Meanwhile, the black mamba escapes and bites the maid, who dies.

Venom
Terrorists fleeing to a deserted home to abduct a child are met with a deadly surprise as a venomous serpent emerges, putting their own lives at risk.