For other uses, see Thriller (disambiguation).

The thriller is a genre of fiction in which tough, resourceful, but essentially ordinary heroes are pitted against villains determined to destroy them, their country, or the stability of the free world. The hero of a typical thriller faces danger alone or in the company of a small band of companions. The protagonist may be a law enforcement agent, a journalist, or a soldier, but typically he or she is cut off from the resources of "their" organization. More often the hero is an ordinary citizen drawn into danger and intrigue by circumstances beyond their control. Thrillers are typically novels or movies, though television series such as Alias and 24 (US), and The Sandbaggers (UK), also fall into this genre, along with such non-fiction bestsellers as Holy Blood, Holy Grail and even Fermat's Enigma, Simon Singh's account of the conquest of Fermat's Last Theorem. While thrillers constitute a distinct genre, they often incorporate elements of other genres such as adventure, detective fiction, and espionage. A thriller includes suspense as an indispensable ingredient.

Novelists closely associated with the genre include: Eric Ambler, Desmond Bagley, John Buchan, Frederick Forsyth, Jack Higgins, Christopher Hyde, Duncan Kyle, Alistair MacLean, Dan Brown and Robert Ludlum.

Notable movie thrillers include: The Thirty-Nine Steps, North by Northwest, The Day of the Jackal, Duel, The Parallax View, In the Line of Fire, and The River Wild.