The youngsters will star alongside Aaron Eckhart and Vera Farmiga in the biopic based on the last six years of the life of Beach Boys drummer Dennis Wilson.
Moretz (pictured) will play Wilson’s daughter Jennifer and Grint, in an early outing after the Harry Potter franchise, will play Stan Shapiro, a William Morris intern who becomes a close friend to the musician.
Randall Miller will direct from Jody Savin’s screenplay and the pair are producing The Drummer under their production label Unclaimed Freight Productions alongside Brad Rosenberger, the former Warner-Chappell Music Group executive who brought in the project.
Production is set to commence in southern Georgia on Jun 15 to coincide with the 50th anniversary of the Beach Boys.
W2 is co-financing the project and represents international sales. Gerry DeKlerk and Irene Nelson of Rampart Films serve as executive producers alongside Jim Guercio of Caribou Records.