'Parenthood' alum Jonathan Tucker has also joined the cast of the drama from Bryan Fuller and Neil Gaiman.

Starz's American Gods adaptation is adding to its cast.

Crispin Glover (Back to the Future) and Jonathan Tucker (Parenthood) have booked key roles in the drama from Bryan Fuller and Neil Gaiman.

The drama centers on a war brewing between old and new gods: The traditional gods of biblical and mythological roots from around the world are steadily losing believers to an upstart pantheon of gods reflecting society’s modern love of money, technology, media, celebrity and drugs. Its protagonist, Shadow Moon (The 100's Ricky Whittle), is an ex-con who becomes bodyguard and traveling partner to Mr. Wednesday (Ian McShane), a con man but in reality one of the older gods, on a cross-country mission to gather his forces in preparation for a battle with the new deities.

Glover will play Mr. World, the seemingly omniscient leader at the center of the New Gods coalition, sometimes more challenged by his own subordinates than his enemies. In keeping an eye on the activities of the Old Gods, he realizes that their ringleader, Mr. Wednesday, poses an imminent threat.

Tucker will play Low Key Lyesmith. Shadow's one confidante in prison, Low Key is a surprisingly philosophical individual. Wiry and fast talking, with an offbeat sense of humor, he has a theory for everything and gives Shadow some sage advice to ready him for the outside world.

They join a cast that also includes Emily Browning as Laura Moon, Sean Harris as Mad Sweeney, Yetide Badaki as Bilquis and Bruce Langley as Technical Boy. American Gods begins shooting next week.

Glover's credits include The Doors, Hot Tub Time Machine and Alice in Wonderland. American Gods will be his largest TV role to date following his role in History mini Texas Rising. He's repped by APA.

Tucker, repped by UTA, counts DirecTV's Kingdom and NBC's Parenthood among his credits. The casting reunites him with showrunner Fuller following a two-episode arc on NBC's Hannibal.

Fuller and Michael Green (The River) will pen the script and serve as showrunners on the FremantleMedia North America project. David Slade will direct the pilot and additional episodes. FMNA's Craig Cegielski and Stefanie Berk will executive produce alongside Fuller, Green, Slade and Gaiman. Starz senior vps original programming Marta Fernandez and Ken Segna will oversee for the network.