I was expecting the civilians to pull the trigger, but instead of it blowing up the convicts, it would blow up their own boat or release a gas or something. Y'know ... something twisted.
Would have been better if it was rated R. Like when the police helicopter goes down and the cop in the SWAT van is like "oh no, this is not good." You know he'd be screaming his head off, like "what the fuck is this shit, omg we're gonna die!"