Take three gifted comic actors, put them in a situation rife with hilarious potential with the guy who directed "The Devil Wears Prada" and you get - baited and switched, at least in the case of "The Big Year."

　　 It's not that there's anything particularly wrong with David Frankel's adaptation of Mark Obmascik's book about competitive birding. In fact, there's a lot that's right with it, starting with the cast: Jack Black plays Brad Harris, a 30ish underachiever living with his parents in Baltimore; Steve Martin is Stu Preissler, a wealthy tycoon who uses bird-watching as a way to escape the torpor of retirement; and Owen Wilson plays Kenny Bostick, whose most recent Big Year - when birders try to see as many rare species as they can - racked up a record 732 sightings.

　　 When Brad and Stu make a run at Kenny's record, the game of "The Big Year" is afoot, taking the three as far afield as the Aleutian Islands, the Florida Everglades and points in between. Granted, Frankel has stinted on nothing, taking his cast to real-life locations, once in a while giving the audience a glimpse of their beautiful, flighty quarry.

　　 But somehow, the comic chemistry never seems to ignite in "The Big Year," which burbles along at the clunky pace of a low-stakes chase; issues of male ego, （英语影评）competitiveness and compensation are briefly addressed but never truly engaged, and too often, the three actors look and feel as if they're in three different movies. (More than "The Devil Wears Prada," "The Big Year" resembles Frankel's last film, the warm, fuzzy and bland "Marley and Me.")

　　 Quiet, genial and mild-mannered to a fault, "The Big Year" has the virtue of being deeply un-cynical, but at the expense of propulsive vigor, structural elegance and behavior that's recognizably human as opposed to engineered in Hollywood. "The Big Year" has heart and sweetness to spare - but as any birder will tell you, focus and energy count, too.