Michelle Williams Back in New York City

02/11/2008 at 03:15 PM EST

Days after taking a plunge in the ocean following Heath Ledger's wake in Australia, Michelle Williams is back in New York City.

The actress, who had been shooting the film Mammoth before her ex's untimely death, was spotted Monday in SoHo outside the nature store Evolution, where the film is currently shooting. (The store features skeletons, medical posters and other trinkets.)

Over the weekend, Williams and at least 50 other mourners all ran onto the sand – and many of them jumped in the ocean – behind the Indiana Tea House on Cottesloe Beach, the site of the wake and one of Ledger's favorite spots.

Williams, still wearing her sundress, briefly went into the water as everyone cheered.