‘The Night Listener’ is a shaggy-dog story

You never know where Robin Williams is going to pop up next, or what genre or budget or co-star he’s going to try on for size.

He poured on the schmaltz as David Duchovny’s mentally challenged pal in “The House of D.” He was curiously lame as an editor with a gift for creating white lies in “The Final Cut.” And he was literally showered with excrement in the recent “family” comedy, “RV.”

Every so often he does something that reminds us why he’s regarded as not only a brilliant comic but a gifted actor. It hasn’t really happened since “One Hour Photo” four years ago, but it comes close to happening again in Patrick Stettner’s uneven and overlong (at 82 minutes!) adaptation of Armistead Maupin’s novel, “The Night Listener.”

Quick facts Starring: Robin Williams, Toni Collette, Sandra Oh, Rory Culkin, Joe Morton Director: Patrick Stettner Run time: 1 hour, 22 minutes MPAA rating: R

Williams gives one of his more thoughtful performances as Gabriel Noone, a popular gay writer whose longtime lover, Jess (Bobby Cannavale), has just left him. Gabe reads his stories on a late-night radio show, but his situation has become so desperate that he develops a bad case of reader’s block. He no longer believes in the stories he’s telling over the air.

At the same time, he finds himself becoming attached to a dying 14-year-old listener, Pete (Rory Culkin), and his foster mother, Donna (Toni Collette). Their relationship is strictly by phone because they’re in Wisconsin and Gabe is in New York. As Jess points out, Pete and Donna sound much alike on the phone; he even introduces the idea that Gabe could be dealing with a split personality.

What if Pete is like Norman Bates in “Psycho,” expertly playing both himself and his mother? What if he’s dead? What if he never existed, and what if Donna is responsible for the hoax? The movie tells us at the outset that it’s based on a true story, and an epilogue spells out some of what happened. But in the end the identity of  the boy (and Donna) is as much a mystery to us as it presumably is to Maupin.

The script (by Maupin, Terry Anderson and director Stettner) toys with the notion that all of this could be in Gabe’s mind. He’s stressed out, he’s reached dead ends in his personal and professional lives, and perhaps he needs an imaginary playmate so much that he’s created one.

As they enter “A Beautiful Mind” territory, with Culkin playing a character who may be pure fantasy, the filmmakers sometimes falter. There’s not enough material to hold this shaggy-dog story together, and they start adding filler: a wry plane conversation with a flight attendant, an episode in which Gabe is mistaken for a pedophile, a grim exchange with his bigoted father, exposition-heavy scenes with Gabe’s sounding boards (Sandra Oh, Joe Morton).

Nevertheless, Williams is frequently at his best here, drawing us into Gabe’s dilemma, providing some insight into the reasons for Jess’ estrangement, and making every scene with Collette count. When these two finally do connect, the reasons may be murky, but the performances are confident and genuine.

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