A warning upfront: For anyone who's lost a parent, watching Anand Tucker's beautiful new film, "When Did You Last See Your Father?" will be a gut-wrenching experience. Based on the memoir by British writer Blake Morrison, it's a film about losing a father, but it also covers the complicated relations with that father all along.

Sensitive viewers will be weeping buckets by the film's end, and that's precisely why it's so comforting to have Colin Firth, what with those doleful brown eyes, on hand. Firth plays Blake circa 1989, by then a successful novelist and poet. But this being a film that shifts between decades, there was a need for more age-appropriate casting: Bradley Johnson and Matthew Beard portray a bookish and somewhat timid Blake as child and teen.

Blake's father, Arthur (played with gusto by Jim Broadbent), is the life of the party, a loudmouth who constantly refers to his son as "fathead." As a child in the 1950s, Blake regards him as "invincible." But by the time Blake reaches his teens, in the 1960s, he catches wind of his father's infidelities and so grows to resent, if not outright hate, the man.

By the time Arthur learns that he has terminal cancer, things have cooled between the two. And yet, Blake wrestles with questions about his father's character: After all this, can he remember his dad fondly? And for that matter, when was the last time he truly saw his father as wholly himself, without the polluting influence of cancer? These are the themes that break a moviegoer's heart.

It's maddening, however, that the story shows so little regard for its leading lady. The suffering of Blake's mom, Kim (Juliet Stevenson), is portrayed in small ways, but mostly she's on hand to do the dishes or offer her son the occasional supportive, if dumbstruck, glance. Other female characters are more fully human but, in carrying on the great tradition of fictional mothers, Kim's sole purpose is serving others -- even as she suffers the ultimate loss.

Still, this is a quiet and quite gorgeous film, shot in faded grays and blues -- the colors of memories. As with all great art, it doesn't draw conclusions or brandish an obvious moral. In fact, few films end on such a tender note. It can be painful to watch as it so painstakingly captures the slow process of loss -- from that moment the child leaves for college, up until the exact second of a father's last breath. But it's worth every last teardrop.