Film review: Mark Ruffalo's bipolar dad charms in Infinitely Polar Bear

An autobiographical movie with which first-time writer-director Maya Forbes fondly remembers her manic-depressive father, Infinitely Polar Bear features an endearing turn by Mark Ruffalo and will bring a smile to your face.

Largely omitting the darker moments in the core family of four, this Boston-set yarn begins with one of its few alarming scenes when Cam Stuart (Ruffalo) has a breakdown in front of his wife, Maggie (Zoe Saldana), and their two daughters, Amelia (Imogene Wolodarsky) and Faith (Ashley Aufderheide).

After a brief period in an institution, Cam is released to live away from home. But as Maggie — the imposed breadwinner due to her husband's inability to hold down a job — enrols herself in a New York grad school, Cam is entrusted to care for the children for 18 tough months.

Although his wealthy family apparently refuses to help out, there's no lingering sadness in the outgoing Cam and his kids as they keep themselves busy with his overzealous attempts to befriend their neighbours.

With half-finished handcraft projects lying all over the place, Cam's cramped apartment is like a character in itself.

Intimate and surprisingly funny, the film is at its most charming when the spirited girls, while struggling to make sense of their father's erratic behaviour, show him immense affection. As mental illness dramas go, Infinitely Polar Bear is probably among the most cheerful of the bunch.

Infinitely Polar Bear opens on June 25