Good acting saves ‘Bug’ from the fly swatter

William Friedkin’s latest thriller, “Bug,” has a clear advantage over most of the summer movies: it’s not a sequel, a spinoff or any other kind of retread. Best of all, it doesn’t tell you exactly where it’s going until it’s almost there.

On the other hand, what begins as a fairly naturalistic five-character drama eventually turns into a full-blown horror film filled with outrageous conspiracy theories, earthquake-like tremors and visions of an apocalypse that has been planned by evil politicians since 1954.

Long before it’s over, you may feel more duped than provoked by Tracy Letts’ screenplay, which is based on his off-Broadway play. After lulling you into accepting the characters as recognizable and understandable, the script suddenly takes them to extremes. Still, it’s quite a ride if you can survive all of those treacherous curves.

Quick facts Starring: Ashley Judd, Michael Shannon, Brian O'Byrne, Lynn Collins Director: William Friedkin Run time: 1 hour, 42 minutes MPAA rating: R

The heroine, Agnes White (Ashley Judd), is a depressed, aging waitress whose options have become increasingly limited. Years before, she lost her six-year-old son in what appears to have been a grocery-store kidnapping, and she’s on the outs with her abusive, recently paroled ex-husband, Jerry (Harry Conick Jr.), who could be harassing her with ominous phone calls.

She appears to be enthusiastically involved with a lesbian waitress, R.C. (Lynn Collins), as the movie opens. But she’s more attracted to men, especially an asexual loner, Peter Evans (Michael Shannon), who says he wants only to be her friend. This sounds like the best offer she has, and she takes it. She has no idea how crazy their relationship will make her.

In the beginning, Friedkin’s cameras hover almost randomly above the deteriorating motel room where Agnes lives — hinting, like the opening of Hitchcock’s “Psycho,” that they might land anywhere. There’s something accidental about the selection the cameras make, yet there’s also something inevitable about the connection Peter and Agnes make.

These opening scenes, which provide a strong sense of the environment the couple shares, are the most believable and cinematic episodes. But at some point “Bug” loses this quality and begins to feel like a filmed play. The characters stop revealing themselves and start making demands and issuing ultimatums.

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The result is a hybrid, worth seeing mostly for the performances, which are consistently strong. Connick could be auditioning (successfully) for Stanley Kowalski in a remake of “A Streetcar Named Desire,” while Shannon, who played this role on stage, is wonderfully still and spooky, like a 21^st Century Norman Bates.

Judd, coming off a series of hugely commercial women-in-peril movies (“Kiss the Girls,” “Double Jeopardy”), digs deep to discover the contradictions in Agnes, whose dilemma becomes increasingly poignant as she joins with Peter to face the abyss. At times, you can’t help feeling that this is the role she was born to play.

First shown at last year’s Cannes Film Festival, “Bug” is Friedkin’s most watchable movie in years. He may be a long way from the glory days of “The Exorcist” and “The French Connection,” which won him a best-director Oscar, but he still has a way with actors.

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