A film with more than the usual spoiler issues. Talking about it in any detail feels akin to handing you a gift-wrapped present and saying, "I hope you like it -- It's a thriller about a diabolical secret experiment."

It's funny, it's tense, it features two great performances from two actors and the director expertly creates a web of odd tension where you actually don't know what is happening for the majority of the run time.

The best films of this genre always show a path and provide a takeaway for being a better person.

The storyline feels a little thin and moth-eaten in parts but this sequel is plenty of fun.