The new disaster flick Contagion sports an all-star cast including Matt Damon, Jude Law, Gweneth Paltrow and Kate Winslet. It sports an Academy Award-winning director in Steven Soderbergh.

It also sports this truly spectacular viral ad campaign (I’m so sorry for that, everybody).

In the weeks before the worldwide premiere, Warner Bros. Canada Google+Feedfetcher”>hired the ad company Lowe Roche to make two unique billboards to promote the film.

The two billboards that were created actually served as giant petri dishes. They were laced with different bacteria and fungi and hung in a storefront window in Toronto.

As you can probably guess, as the bacteria and fungi grew, they spelled out “Contagion” on the billboards.

I must say, this is one of the coolest marketing campaigns I’ve ever seen. Check out the video for some awesomely disgusting fun –

The first 50 people to view the bacteria-board received free passes o the film, which opens today. Right now, it’s 81% certified fresh on Rotten Tomatoes, so it look like this might be a pretty big end-of-summer blockbuster for Warner Bros.