Crabbe and Goyle

Vincent Crabbe and Gregory Goyle are Slytherin students in Harry's year; both of their fathers, Crabbe Sr and Goyle Sr are Death Eaters. Due to their size and strength, the pair act as Draco Malfoy's minions and serve to intimidate fellow students. Crabbe and Goyle are both brawn-over-brains type; they are entirely lacking in introspection or inquisitiveness. They seem unable to make up their own minds or to see things their own way; they generally act upon Malfoy's instructions. Nonetheless, Crabbe is depicted as slightly more intelligent than Goyle; in Philosopher's Stone, he is handpicked by Malfoy as his second in the Midnight Duel with Harry that never takes place.
Crabbe and Goyle makes their first and only appearance as new Slytherin Quidditch Beaters in the opening match against Gryffindor in their fifth year; after Harry catches the Snitch, Crabbe vents his frustration by purposely hitting a Bludger into Harry's back and knocking him off his broom, but receives the light punishment of writing lines. They do not return to the team the following term, as they regularly serve as Malfoy's lookouts during his forays into the Room of Requirement. After Malfoy leaves the school following the death of Dumbledore just before the end of the term, Crabbe and Goyle are left in a state of loneliness.
The three of them are reunited in Harry Potter and the Deathly Hallows. Both of them speak for the first time, Crabbe's voice being described as "oddly soft for someone with his huge frame" and Goyle's simply as a grunt. Crabbe has sided with the Death Eaters with more conviction than either Goyle or Malfoy, and becomes increasingly independent of Malfoy, well aware of the Malfoy family's falling out of favour with Voldemort. The pair have developed into surprisingly powerful wizards. Crabbe and Goyle are mentioned as having excelled in inflicting the Cruciatus Curse on other pupils under Amycus Carrow's direction: according to Neville Longbottom, it was "the first time they were the best in anything." However, while Crabbe gains superficial knowledge of many powerful Dark spells, he neglects to take their potency seriously. During the fight for one of the Horcruxes (Ravenclaw's diadem) with Harry, Ron and Hermione in the Room of Requirement, he defies Malfoy's order to not kill Harry and casually throws around the Avada Kedavra curse. Finally, he summons Fiendfyre and turns the room into a blazing inferno, but it quickly rages beyond his control and ultimately leads to his demise. Crabbe's spell, ironically, destroys the Horcrux. Goyle is knocked unconscious during the ensuing fight, but is rescued along with Malfoy by Harry, Ron and Hermione. Goyle and Malfoy are left mourning Crabbe's death. This scene marks Goyle's last mention in the series, and his final fate is unknown.
Jamie Waylett and Joshua Herdman have respectively appeared as Crabbe and Goyle in all of the Harry Potter films to date.