El único sobreviviente de una masacre sangrienta debe unirse a un grupo variopinto de policías novatos y delincuentes para defender una estación de policía de una invasión de monstruos de otra dimensión.

A couple of hippies are searching for Joe, an old friend who apparently never aged a day since they were young. Through technicolor ninjas, bizarre metalheads, shamans and ancient rituals, the two embark on a journey with no turning back.

Sophie's 18th birthday becomes a bloodbath when monsters descend upon her house and start to devour the party guests. Sophie and her friends must rally together to send their party crashers back to hell.