The Thuggery Affair is the sixth in a series of novels about the modern Marlow family by children's author Antonia Forest, first published in 1965.

The action is set mainly in Colebridge, the nearest town to the Marlow family's home at Trennels, during spring half-term.

Jukie, the gang leader, requisitions Miss Culver's car and attempts to escape, taking Patrick with him.

The Thuggery Affair was relatively unsuccessful compared to other books in the series, being printed in only one hardback and one paperback edition during Forest's lifetime; it was finally reprinted by Girls Gone By in 2005.

Commenting on the book, Antonia Forest explained it was, 'written during that long-dead period when teenagers talked self-invented languages, incomprehensible to any other age-group.