Balancing mental illness with comedy can be a precarious undertaking. Filmmakers who shoot for a direct and straightforward comedy have an easier time, but those mixing elements of humor with a more dramatic lean can sometimes subvert the aim of their film. “Infinitely Polar Bear” is an example of a movie taking a more dramatic look at mental illness but lacing it with smart, responsible humor which doesn’t overthrow the film’s purpose.

Maya Forbes writes and directs this semi-autobiographical portrayal of her life living with her bipolar father. Forbes created a fictionalized version of herself and cast her own 12 year-old daughter Imogene Wolodarsky for the role. She sets her film in Boston sometimes in the late 1970s and chronicles a year of intense ups and downs brought on by her father’s bipolar disorder.

The film begins with Cam Stuart (Mark Ruffalo) in nothing but red briefs and a red bandana banging on a car as his wife Maggie (Zoe Saldana) and their two children (Wolodarsky and Ashley Aufderheide) sit terrified inside. The initial absurdity tempts us to laugh, but Forbes quickly acquaints us with the reality of the situation. Cam has had a serious mental breakdown. He loses his job and is sent away for rehabilitation. As a result Maggie has to move into a low-rent apartment where she struggles to provide for her daughters.

Over time Cam progresses and is soon moved to a halfway house where he has an opportunity to reconnect with his daughters. Unable to sufficiently provide for her family, Maggie decides to go back to school to get her M.B.A. and eventually a better job. But that would require Cam to take care of the kids during the week while she is away at Columbia. His doctor thinks the responsibility would be good for him. Maggie is desperate. Cam reluctantly agrees.

The bulk of the film focuses on this mentally frail father getting by on lithium and cigarettes while trying to relate to and take care of his two young girls. There are numerous opportunities for humor and Forbes gives them to us, but you can sense her personal touch on the story and the characters. Cam isn’t a mean-spirited lout or a target for our judgements. It’s clear he represents the real-life father who Forbes truly loves. At the same time she doesn’t gloss over the realities of their struggles and the film is better due to that honesty.

It also works thanks to some strong performances particularly from Mark Ruffalo. Ruffalo is a guy who is always solid but who is often defined by his laid-back and relaxed performances. Here he is given material that allows for him to expand himself. One minute Cam can be even-tempered and playful while the next may see him wound tighter than a top. When things get stressful we see him impulsively bouncing from one mood to the next, his kids often being the victims. Ruffalo handles it all with such authenticity. Saldana is also very good it would could be a thankless role. It’s Ruffalo that gets the spotlight but Saldana’s earnestness is crucial.

In the end “Infinitely Polar Bear” succeeds in looking at mental illness with a careful mix of humor and drama. There are portions of the story that feel shortchanged and the film sometimes seems uninterested in plot points that I would like to know more about. But Forbes stays true to the heart and soul of her movie and her connection to the subject matter shows itself in the pleasing end results.

VERDICT – 4 STARS