Simon Says (2007)

Five college friends choose to spend their vacation debauching at the riverside. They find the perfect place to camp out, but end up crossing paths with twin brothers, Simon and Stanley. The twins then begins to knock off the campers in some extremely creative (and extremely gruesome) ways.
William Dear, Colin Michael Kitchens
Crispin Glover, Margo Harshman, Greg Cipes, Kelly Vitz, Carrie Finklea, Artie Baxter, Lori Lively, Bruce Glover, Blake Lively, Oliver Dear, Leila Johnson, Erica Hubbard, Bart Johnson, Daniella Monet, Kelly Blatz, Dean Shelton, Ernie Lively, Robyn Lively
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