It has been nearly ten years since the debut film of the writer/director Tamara Jenkins. Slums of Beverly Hills was feisty, funny and occasionally filthy; it earned a minor cult following and it marked Jenkins as a talent to watch. Whatever the reason for her protracted absence from the screen, one thing is certain: while she has lost none of her bittersweet wit, Jenkins has gained a maturity and an emotional depth that serves her well. The Savages, her second feature, is a triumph – an impeccably acted and beautifully observed study of the end of life, spiked with refreshingly irreverent gallows humour.

If the quality of acting talent in a film can be used to gauge the quality of the script, then Jenkins could hardly have hoped for a more ringing endorsement than the casting of Laura Linney and Philip Seymour Hoffman in the two main roles. Unquestionably two of the greatest character actors of their generation, Linney and Hoffman bring the kind of commitment to the roles of siblings Wendy and Jon Savage that carves them out as flesh-and-blood human beings, rather than just shadows on a screen.

Linney’s Wendy is an aspiring playwright who spends her time begging for grants, using the stationery stolen from her temporary jobs. She is involved in an affair with a married man who hauls along his ailing labrador as an alibi. Tellingly, the most convincing moment of tenderness we glimpse during a tryst is when Wendy absent-mindedly reaches out and strokes the long-suffering dog’s paw.

Her brother Jon is a shambling academic whose laconic persona occasionally cracks into self-pitying melancholy. He is unable to commit himself to his Polish girlfriend but weeps silently at the sight of the plate of eggs she cooks for him for breakfast. Brother and sister are united by a mutual impatience with each other and a shared sense of disappointment in their parents.

It’s the plight of one of their parents that brings Wendy and Jon back together. Their father’s cantankerous nature has become uninhibited by the onset of dementia; his lavatory-based act of rebellion is too much for the picket-fenced Arizona retirement community where he lives. When Wendy comes to collect her father (a superb performance from Philip Bosco) she finds him lashed to a hospital bed. He’s sent off to his new home with too-bright smiles and a stash of nappies for grown-ups.

It is a turning point in all adults’ lives if they find themselves responsible for the care of a parent infantilised by illness. For Wendy and Jon, this is complicated further because their father so manifestly failed them in his own role as care-giver. The brilliance of Jenkins’s complex, carefully judged film is that, however bleak its candour about the humiliations of death, it is never mawkish and has a pitch-black humour. There is also a satisfying sense of a rite of passage: the characters we leave at the end of the film are still flawed, but perhaps more fulfilled.

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