College student Zibby (Elizabeth Olsen) falls for 35-year-old Jesse (Josh Radnor) in “Liberal Arts.” Guess who wrote it.

When Josh Radnor isn’t busy trying to find the love of his character’s life on “How I Met Your Mother,” the 38-year-old actor is an auteur filmmaker. Radnor has written, directed and starred in two independent films: 2010’s “Happythankyoumoreplease” and this year’s Sundance favorite “Liberal Arts,” which opens Friday.

In the film, Radnor plays Jesse Fisher, a 35-year-old admissions counselor at a New York college who’s feeling stuck — until he takes a trip to his alma mater, a small liberal-arts school in Ohio. There, he meets a spunky 19-year-old named Zibby (Elizabeth Olsen); a troubled student (John Magaro) who reminds Jesse of himself; and a sage, probably stoned wanderer played by Zac Efron. The trip rejuvenates Jesse, who begins a courtship with Zibby.

You shot “Liberal Arts” at your alma mater, Kenyon College. Did that prompt any revelations similar to the ones Jesse has in the film?
I haven’t really gone through what Jesse had gone through. When I got the idea [for the film], I wanted to create a character who really hadn’t gotten over college and was spinning his wheels. [Shooting there], I was both publicly celebrating my college and my experiences there and also saying goodbye to it.

What kind of student were you when you went to Kenyon?
When I got into Kenyon, I was surrounded by all these sharp, funny, voracious readers who were sharper and funnier than I was. I started reading a lot more for pleasure, upping the kinds of [books] I was reading. Jesse’s enthusiasm for British Romantic literature, I share that with him. I just found the whole experience really challenging. Eighteen to 22, those are tough years, no matter where you are.

Jesse and Zibby write letters to each other about classical music. Are you a letter writer?
Whenever I get a handwritten letter, I find it to be this touching event, like, “Oh my God, someone put pen to paper!” I’m a big emailer, but I think there is something romantic about people writing by hand. In some ways, this kind of lost or dying form was a central theme of the movie — making a case for these possibly fading things. Things are changing so fast, but there’s still this sturdy sensibility to this college that was founded in 1824 and hasn’t changed much.

The Sage Shaman

In “Liberal Arts,” Zac Efron takes a surprisingly comedic turn as Nat, a hippie wanderer whom Jesse (Josh Radnor) crosses paths with. In a way, Nat acts as Jesse’s spirit guide, offering shamanistic advice. “The trap with that part is people would play it really ironic,” Radnor says. “I needed an actor who would play it sincerely, in a really big, honest, open-hearted way.”