Yes, I meant the more recent Cold Comfort Farm, 5 or 6 years ago -- made for British TV but a US theatrical release. Eileen Atkins and Ian McKellen and Joanna Lumley were also in it, with Kate Beckinsale as the protagonist. Rufus Sewell is striking and handsome here as elsewhere but is physically substantial (which is perfect, because he looks at home working the farm, but when he utters his unlikely dream, you think "Yeah, he could be a movie star").
His big bid as American movie stardom was Dark City, a pre-Matrix everything-is-an-illusion sort of SF cult film. He had almost the only big role in that (Kiefer Sutherland and Jennifer Connelly were also in it).
He originated the role of Septimus in Stoppard's Arcadia in London; Billy Crudup (in his professional debut) created the same role in NY. Both actors were being touted as "the next big movie stars" for the next few years. Neither one has made it, but not I think through any personal lack -- they're just interested in other things as well.