CBS Films’ romantic comedy also stars Zoe Kazan, Mackenzie Davis and Rafe Spall
The film was formerly titled “The F Word,” and finds Radcliffe's character stuck in the friend zone as Kazan's character already has a boyfriend.
Adam Driver and Mackenzie Davis co-star alongside Rafe Spall and Megan Park.
“What If” premiered at the Toronto International Film Festival last year and will hit U.S. theaters in August.
Watch the trailer below to find out what snack Driver's character enjoys after sex.