Eugene O'Neill's brief but powerful play about a coal stoker on a trans-Atlantic ocean liner has survived long enough to be credibly produced by the Marin Theatre Company because O'Neill flirted with socialist themes but never made them the core of his play. He knew there was more to a man than his role in society. For this revival, director Lee Sankowich has cast Aldo Billingslea, who's black, in the lead role of Yank, who's traditionally white. When a rich young woman takes a tour below deck to see "how the other half lives," she finds Yank at the fire, sweaty, enraged by something, and about to fling his shovel. She faints. Later she calls him a "hairy ape," but not before Yank has fallen for her so hard that the insult feels unforgivable; he scours Manhattan to find her. Yank's introduction to high society -- and socialist politics -- only inflames him. Billingslea does excellent work, especially with Yank's passionate speeches, although some of his unimpassioned lines are awkward. Sankowich's casting choice adds a welcome new dimension to the show. This play was an early experiment with expressionism for O'Neill, so it's laden with unrealistic and sometimes heavy-handed symbols. Yank's shipmates chant like a Greek chorus, for example, and anonymous rich folk on Fifth Avenue wear commedia dell'arte masks. Also, light shoots harshly through John Wilson's steel-girder set, giving the play the look of a WPA mural -- all angular, unsubtle gesture, which isn't a bad description of the play itself.