But the movie's actors say there's other things to draw an audience.
"We got boobs, we got blood and gore. What more can you want in a movie?" says cast member, Riley Steele. "And it's in 3D! I mean, come on!"
In "Piranha 3D," a little earthquake unleashes some prehistoric piranhas into a lake just in time for spring break.
"There are many scenes in this film that people will be watching with their hands covering their eyes," says Josh Stolberg, the film's co-writer.
"One is soft and gentle and cute and the other draws blood," she says. "Mine draws blood."
"You know, I have marks all over my body," O'Connell added. "Not from piranha, but from Rebecca."
The humor website, Funny or Die, put up a "Piranha 3D" "for your consideration" Oscar pitch. All in good fun, right?
"There's enough CG in this movie to nominate us for best animated feature, so watch your back, Pixar," says actor Adam Scott in the video.
"I think I deserve an Oscar, so this is definitely going to be the film where I finally get what I deserve," added Shue.
"Piranha 3D" has its vicious moments from man and from beast, but if you're still not quite convinced.
"We all do have some interaction with piranhas at some point in the movie where we are completely covered in blood," Brook says.
"I mean, I think this is a film that definitely tests boundaries and I think that's why I signed onto it, you know?" says actor Steven McQueen.
"Piranha 3D" is rated R. It opens Friday.