50/50 was reportedly inspired by screenwriter Will Reiser’s (Assume the Position 201 with Mr. Wuhl) actual battle with cancer, but it has an oddly impersonal feel to it. If it’s an autobiography (or semi-autobiography), it’s an autobiography filtered through a lens of convention. It retains the shadow of depth, but there’s a curious weightlessness to it.

Apparent author-surrogate Adam (Joseph Gordon-Levitt, Inception), a twenty-something-year-old reporter for a Seattle public radio station (Movie protagonists never have regular jobs, do they?) with an underdeveloped tendency to be overly cautious (He doesn’t drive, although he’s willing to ride in a car) has been having back pains.

When he consults his physician, he learns he has a rare form of spinal tumor and a 50/50 chance at survival.

Most films would send Adam off on an epic quest — to find meaning, reconnect with loved ones, complete a bucket list, etc. — but 50/50 takes a much more low-key approach, which is simultaneously its strongest trait and the reason the film, ultimately, hardly registers.

Adam, who never becomes anything more than a generic, blandly nice, sad-sack indie protagonist (with cancer only compounding the expected girl troubles), is stuck in a state of denial or mild depression throughout most of the film, which Gordon-Levitt doesn’t make very interesting to watch.

Cancer aside, the film doesn’t offer much in the way of drama. Adam has some issues with his girlfriend (Bryce Dallas Howard, The Help, in an unlikable one-note performance). He has the predictable love interest (Anna Kendrick, Scott Pilgrim vs. the World). He learns to loosen up a bit and gets high with some other patients. Rinse and repeat.

But while the film may be dramatically inert, it has enough comedic charms to justify its existence. The film has a strong supporting cast, and can coast by on their affability.

Seth Rogen (Take This Waltz) is exactly as entertaining as he usually is, and his profane stoner shtick is a nice contrast to Gordon-Levitt’s uptight performance. Philip Baker Hall (Mr. Popper’s Penguins) makes a welcome appearance as an older cancer patient who offers Adam some pot. Kendrick plays the same character she did in Up in the Air as Adam’s shrink-turned-potential lover, but it works as well here as it did there.

The film succeeds, if only barely. It’s an enjoyable, amusing film, but one that feels undoubtedly minor and standard-issue.

rgifford@umdbk.com