Blake Lively fights off a Great White shark in Aussie waters in The Shallows trailer (yes, she's in a bikini)

Blake Lively lives out every Australian vacationer's worst nightmare in the first trailer for The Shallows.

In the clip, the 28-year-old plays a surfer named Nancy, who's all chill at her sweet surf spot on an Australian island, when she's suddenly terrorised by a Great White shark.

But although she manages to swim away as other surfers are brutally killed, she ends up stranded on a rock 182m away from shore as the shark circles around her. Cue Jaws theme.

Yep, it's not exactly a tourism ad for Australian beaches.

The actress, who shot scenes for the movie on Lord Howe Island just 10 months after the birth of her baby James, shared plenty of idyllic island snaps from the New South Wales location back in November.

Here she is posing on her rock…

Bonding with a seagull…

And achieving ultimate surfer chic #hairgoals...

Yep, we'd still vacay there.

The Shallows hits Australian cinemas on August 18, 2016.