Kristen Stewart has never been an actress known for her smoldering passion. Bella Swan, the character to which she'll forever be linked, is a picture of repressed sexuality in the 'Twilight' films. But like her 'Twilight' co-star (and current boyfriend) Robert Pattinson, Stewart is doing everything she can to break herself out of the mold cast by that popular franchise. Enter 'On the Road.'

The Francis Ford Coppola-produced adaptation of Jack Kerouac's classic just debuted at the Cannes Film Festival and while reviews on the movie are mixed, critics agree on one thing: this isn't your little sister's Kristen Stewart.

If Kristen Stewart were looking for the antidote to the chaste Bella Swan, she certainly found it in Marylou, the 16-year-old lover of 'On the Road' protagonist Dean Moriarty (played here by Garrett Hedlund).  Says Vulture of Stewart's role: "[She] takes her top off so many times that even the perennially shirtless Taylor Lautner would be impressed."

Digital Spy adds in their review, "There are asses and breasts aplenty."

It's a role that would certainly shock the majority of the 'Twilight' audience (in addition to the nudity, Stewart is a willing participant in a number of on-screen sex acts we won't get into here) or those familiar with her public persona, in which she always looks as if she's going to curl into her too-large flannel shirt, like a hipster hedgehog.

When asked about the provocative new role, Stewart said at a Cannes press conference:

I love pushing and I love scaring myself. To watch a genuine [sexual] experience onscreen is so much more interesting than when you see the tape holding up the pasties ... As long as you're being really honest, there's nothing ever to be ashamed of.

But is the movie any good? While Stewart herself is drawing kudos for her adventurous performance, the movie itself is seeing mixed reviews. Our own James Rocchi wrote in his review for IndieWire, "the film feels like any other roadtrip -- no matter how beautiful the scenery flickering by through the window, eventually you just want to get out of the g--damn car."

'On the Road' will hit theaters this fall. Stewart can be seen next in another family-style blockbuster, 'Snow White and the Huntsman.'