The Lord of the Rings trilogy

 The Star Wars trilogy (Episodes 4-6)

 The Godfather trilogy

 The Indiana Jones trilogy

 Sergio Leone's "Dollars" trilogy (A Fistful of Dollars - For a Few Dollars More - The Good the Bad and the Ugly)

 The Star Wars trilogy (Episodes 1-3)

 The Spider-Man trilogy

 The Die Hard trilogy

 The Evil Dead trilogy

 The Matrix trilogy

 The Trois Couleurs trilogy (Blue

  White

  Red)

 The Saw trilogy

 The Jurassic Park trilogy

 The Naked Gun trilogy

 Robert Rodriguez's "Mariachi" trilogy (El Mariachi - Desperado - Once Upon a Time in Mexico)

 The Infernal Affairs trilogy

 The Rambo trilogy

 The Spy Kids trilogy

 The original Ring trilogy