After violence and poverty got out of control in America the government regained control but deemed that each year their would be a 12 hour period known as "The Purge" where all laws get put aside and everything, including murder becomes legal in order to let the population purge themselves of those illegal desires. With those not feeling like they want to participate in the crime spree choosing to hide behind state of the art security systems, security salesmen like James Sandin (Ethan Hawke) have made a fortune off of the vulnerable. But as the annual "The Purge" takes place the Sandin family find their home under attack as their security system is infiltrated and it causes each member of the family to embrace their survival instincts.
Imagine the scene; you have written the script with this idea that in the future there is annual crime spree where you can do what ever you like in order to purge the need from you for another year. You think to yourself it is a good idea as you can't come across another movie with the same idea and so you have devised this home invasion storyline which sees a family locked down in their home full of high tech security surrounded by a club wielding gang whilst inside the house they have issues of their own to contend with.
And that is the problem with "The Purge" as despite an okay set up and some nice touches such as James's son having this tricked out remote control toy the end result is that it is another home invasion movie. As such we have some crawling around in the dark, some near misses and close shaves as well as a psycho but nothing about it really made me sit up and pay attention. In fact with the high tech nature of the Sandin house and James's son doing a lot of hiding and crawling around it reminded me at times of "Hostage", the Bruce Willis movie.
What this all boils down to is that "The Purge" takes an interesting idea surrounding the future and turns it into an ordinary movie which fails to make the most of the situation it sets up. That doesn't mean that "The Purge" is a bad movie but it does mean it is a forgettable one.