It's 6pm in Toronto. The world is scheduled to end at midnight. The unspecified cataclysm that's about to do in the planet has somehow taken away the darkness, so we'll have full daylight up till the end. News of the impending disaster is months old, so the panic has mostly passed, and people, on the whole, are relatively calm. The radio is playing the top 500 songs of all time for, as the deejay's velvet voice soothingly reminds us, "the last night on the planet."

It's an unlikely scenario, this planetary doom, but it's just McKellar's excuse to explore the behavior of people under unprecedented stress, via a small group of Torontonians. Patrick (McKellar) wants to face the end alone, but first he must attend a faux-Christmas dinner (the tree -- decorated, of course -- was shanghaied from a neighbor's yard) with his family. Patrick's mother (Roberta Maxwell) bustles around like everything is fine -- she has even wrapped up childhood mementos from the attic as gifts for her children -- but there's strain under her composure, and she ends up picking on Patrick, ruining her dreams of a perfect last family gathering, as if nagging is all she has left to hang onto. And, indeed, it is.

Patrick's sister Jennifer (Sarah Polley: The Sweet Hereafter) and her boyfriend head off after dinner to join in the carousing in the streets for the biggest party in history. Patrick's friend Craig (Callum Keith Rennie), who believes "we are past modesty," is spending his final hours in his dingy apartment indulging his every sexual fantasy, with enthusiastic help from a bevy of women including one of his former schoolteachers (Geneviève Bujold). But Patrick's solitude is disrupted when he meets Sandra (Sandra Oh: Bean). Desperate to get to her husband -- they had very specific plans for their last evening together -- Sandra is frustrated at every turn when her car is stolen and she is continually unable to find a way across town in the allotted time.

Thematically similar in some ways to 1983's Testament -- which also added to my desire to be right at ground zero, with its depiction of the slow death of a small California town after a nuclear war -- Last Night lacks that film's devastating power but nevertheless joins Testament as one of the few films to look at ordinary people trying to deal with the fact that life would continue to go on even if we were to find ourselves faced with that fact that life wouldn't be going on much longer.

Last Night's script, though, is awkward in spots, and aside from Oh and Rennie -- who are terrific actors -- the cast doesn't particularly distinguish itself. The film's sometimes seemingly random vignettes aren't all brought to satisfying conclusions, and the overall execution has a bit of a messy feel to it. But it has some poignant moments and is ultimately saved by its mordant sense of humor -- Patrick's comment that "we deserved better [cars]"; an "Everything Must Go" sign in the window of a looted supermarket.

As a whole, in fact, Last Night is much more interesting in retrospect, as I find myself returning again and again in my mind to the characters of Duncan (David Cronenberg) and Donna (Tracy Wright), gas-company employees who sadly have nothing better to do than spend the last night in the office; and to Patrick's box of mementos, symbols of a life lived seemingly for nought. And I'm struck by McKellar's ironic final note of hope right at the very end, that a bit of happiness can be found at the moment of defeat. Last Night is a certainly a thought-provoking film, if not a perfect one.