Who voices Wheatley, the personality core in Portal 2?

Stephen Merchant voices Wheatley, the personality core in Portal 2.

Wheatley is an anxious, talkative artificial intelligence who accompanies Chell through much of the game. His nervous energy and constant stream of improvised-sounding commentary contrast with the colder, more controlled personality of GLaDOS.

Valve’s writers created Wheatley’s dialogue with Merchant in mind, praising his distinctive vocal style and ability to deliver frantic comedy. Merchant recorded roughly 16 hours of dialogue and was allowed room to improvise. Early trade-show demonstrations used the voice of Valve animator Richard Lord, which can cause confusion about the final casting.

Another common mix-up involves the game’s other major voices: Ellen McLain voices GLaDOS and Caroline, while J. K. Simmons voices Cave Johnson. Richard Ayoade was considered during development, but Merchant ultimately took the role. Wheatley’s performance became one of Portal 2’s defining comic elements.