It was the premise alone that made me want to see this film, and flaws in execution don't do as much to draw its power away as they could have.

For some reason that's never explained, the world is going to end at midnight, and a disparate group of Torontonians all have different agendas that clash, align and cross, affecting everyone.

Even that description sounds like the same cheesy 'increasingly chaotic group dynamic' we've seen everywhere from Dawn of the Dead to The Divide and everywhere in between.

But it gives the story structure as the movie jumps back and forth between sad sack Patrick (writer/director McKellar) ; his parents and sister (Polley) ; Sandra (Oh), who's just trying to get home to her husband (Cronenberg) and fulfill their final wish together; and Craig (Rennie), who's ticking the last few items off a very personal list.

What keeps these people from their goals is the crumbling social infrastructure around them as much as their own conflicting desires. We meet Sandra ransacking a supermarket slightly frantically, only to lose her car to vandals.

The violence you expect from a social breakdown movie isn't very scary and it's not front and centre because it's not the point – there's a single shocking end for one character but aside from that humanity's unraveling threads are depicted as little more than obstacles.

Patrick spends his last evening with his family, celebrating Christmas (even though it's nowhere near the actual Christmas) and the family discord simmering underneath is only hinted at thanks to Patrick's decision to spend the end alone.

But he finds himself inextricably tied up with trying to get Sandra home and finds the redemption he didn't even know he needed. At the same time, his friend Craig is trying to sleep with everyone he's always fantasised about, including a black hooker and the boys' former French teacher (Bujold).

There are some large holes in the plot – why a prostitute would still be working for money she'll never get to spend makes no sense, and Toronto's not far enough north for it to be broad daylight at midnight.

Those aren't the only narrative niggles, and the performances and plotting are less than stellar, but there's an effective mood of dread and anarchy, hope and hopelessness that run throughout the film.