Eight months ago, Jason Segel bought a Gothic mansion carved into the hill behind the Chateau Marmont. There, in his diminishing free time, the man of the house sips Italian digestifs and composes love songs on the piano. From his upstairs cabana patio, the polite and deferential actor can take in views of his native Los Angeles; he will, oftentimes, do this in the nude. And should he choose to shimmy his hips, his neighbors are treated to a glimpse of what Segel likes to call ''the east-west.''
Wait, was that too much information? If you plan to see Forgetting Sarah Marshall, it better not be. Within the first five minutes of the Judd Apatow-produced flick (out April 18), you too will be acquainted with Segel's nether bits and he's got no problem with that. After all, he wrote the damn movie. ''If you can find the line between sympathetic and creepy, you have reached a very funny area,'' explains the 28-year-old. One hopes he's not talking exclusively about anatomy.
A former state basketball champ, Segel staged a play on a whim while he was in high school, only to be discovered by a Paramount casting agent. He broke into the Apatow fraternity at 19 as hangdog drummer Nick Andopolis on Freaks and Geeks and guested as a hypersensitive boyfriend on Undeclared. More recently, he showed up as Seth Rogen's vulgar housemate in Knocked Up, and since 2005, he's played ever-optimistic Midwestern lawyer Marshall Eriksen on the CBS sitcom How I Met Your Mother. Suggested adjectives for his characters include affable and lovelorn. Plus, says Segel, ''I've been 6'4'' since I was 12. Goofy is somewhere in the lexicon.''
But goofy isn't usually the stuff of marquee men. The studio wouldn't approve Segel for the lead on Undeclared, and he was similarly vetoed from a large role in Apatow's 40 Year-Old Virgin. Hell, he sold his first screenplay at 21 by expressly promising that he would not star in it (the movie remains unproduced). ''When Sarah Marshall got made, Judd put his arm around me and said, 'I'm really proud of you for sticking it out,''' Segel remembers. ''And then he followed it up with 'Because honest to God, if I was you three years ago? I would have blown my brains out.'''
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