A gang of youths have been targeting rural homes in a string of home invasions and burglaries. After one job ends tragically they seek refuge from the huge police manhunt in an old, seemingly abandoned farmhouse.
Unbeknownst to the burglars the house belongs to an elderly serial killer, Mervyn, who divides his time between abducting young women and devising macabre murder devices and traps, putting a sick twist on kiwi ingenuity.
They realize to their horror that they have walked into a decades-old torture palace. The house and surrounding farmland are rigged with fatal DIY booby traps devised to stop victims from escaping.
When the criminals discover two young female victims of Merv's, Dave, the youngest of the group, becomes determined to get them out alive. But the leader, the cold-blooded Kade, has different plans for them and sees the situation as an opportunity. As their ordeal progresses, Kade’s sinister actions will make the audience question who the real monster is.
Now rats in a death maze, will these antisocial criminals work together and use their skills to save themselves and the girls, or will they fall apart and become more victims for “Merv the Perv”?