A few scenes in World's Greatest Dad may qualify it as the most uncomfortable and unsettling movie to sit through of any this year.
Though the first half of the film induces more than its fair share of cringes with sex jokes, pornographic references and inappropriate behavior, it takes a critical turn after a tragic event and shifts from distasteful and off-putting to darkly funny.

Robin Williams plays high school poetry teacher and failed writer Lance Clayton. He is a single dad to Kyle (Daryl Sabara), a loutish kid who hates the world.

Sabara — the little boy from the Spy Kids movies now grown up — is startlingly good at tapping into his inner brat. Deep in the throes of a miserable adolescence, he is a mightily unpleasant teenager, with non-stop attitude and a foul mouth. He is also obsessed with sex in the crudest of ways.

Long-suffering and good-natured, Lance doesn't get any respect at home and very little at school. He does have a fun-loving clandestine girlfriend, Claire (Alexie Gilmore), the school's chirpy art teacher. Lance wants to get more serious, but she prefers to hide that they're dating.

A freak accident leads to disaster. Surprisingly, this is when the film, written and directed by comedian Bobcat Goldthwait, becomes something more satirical and comic. A deception engineered by Lance creates a myth that taps into the complex teenage psyche.

At its best, World's Greatest Dad is reminiscent of the cutting humor of Heathers or Donnie Darko. At its worst, it's exploitative and shocking in its treatment of an essentially taboo subject and its tragic aftermath.

There is a rankling mean-spirited quality to life at school, leavened by a photo of Kyle with a silly expression on his face that takes on increasingly amusing shades as it becomes essentially a marketable commodity.

Williams is excellent and convincing as a discouraged artist who makes some unlikely but understandable choices after decades of feeling creatively stifled. It's his best performance since 2002's creepy One Hour Photo.

Though hampered by an uneven tone and a disturbing conclusion, World's Greatest Dad is a bold, black comedy balanced by an unexpected sense of humanity.

By Claudia Puig
USA Today, August 27, 2009