Warner Bros. and Village Roadshow are mounting the adaptation of Nathaniel Philbrick's novel, which follows the Essex, a whaling ship that was attacked by a giant sperm whale and sank in 1820, stranding its crew at sea for 90 days.
Chris Hemsworth, Ben Walker and Cillian Murphy star alongside Brendan Gleeson, Tom Holland, Frank Dillane and Sam Keeley.
Ikhile will play a sailor named Peterson, while Whishaw is now set to play "Moby Dick" author Melville. TheWrap previously broke the news that he was being eyed for the role.
Howard is directing from a script by Charles Leavitt. Brian Grazer, Joe Roth, Paula Weinstein and William Ward are producing, with Roth Films president Palak Pattel exec producing. Jesse Ehrman is overseeing for WB. Production will start this fall in London.
Ikhile recently starred in the Channel 4 miniseries "The Fear," and his other credits include the popular UK series "Misfits," "Fresh Meat," "Casualty" and "Blackout." He's repped by Identity Agency Group in the UK and Thruline Entertainment in the U.S.
Whishaw, who recently played multiple roles in "Cloud Atlas" and will soon be seen in Terry Gilliam's "The Zero Theorem," is repped by CAA and Hamilton Hodell.