IT'S important to remember the origins of Right At Your Door when popping along to check it out at the multiplex, as, despite its new, glossy trailer, the project is, in fact, a Sundance Film Festival graduate.

This means it's an ultra-low-budget affair, and that the focus will be on a small cast, interesting premise and smart script, rather than special effects or showy scene setting.

It marks a welcome return to the big screen for Mary McCormack, who was excellent in the legendary first series of Murder One back in 1996/7 and then proceeded to fade into televisual obscurity, never capitalising on the possibilities of her ballsy screen presence.

She plays Lexi, a working LA wife who kisses her husband Brad (Dazed and Confused's Rory Cochrane) goodbye one morning in the suburbs, and heads off downtown.

Not long after she has left home, a series of explosions occur, and Brad hears via the radio that some dirty bombs have exploded, creating clouds of toxic gas, which are spreading quickly.

After he ditches his attempts to drive into LA to save his wife somehow, he's instructed by the authorities via the radio to seal the house and therefore quarantine it. And so he leaves a box of clothes and some water by the back door, and he and next door's handyman completely cover and tape up the house.

But then Lexi reappears, covered in ash and desperate to get into her home. Will Brad risk his own health and allow her in?

Satisfaction for the audience comes only at the vaguely twisty conclusion, after quite a lot of shouty, teary drama, making it worth hanging in there for the full 96 minutes.

Where the film is most interesting is in how we can interpret the events depicted, given the current terrorist situation worldwide. Should we believe the instructions given to us by the faceless army or police officials in times of crisis?

Should we rely on media reports so wholly to give us the ins and outs of any situation? Have we really any other option but to do both of the former?