"The Purge 2" is the summer hit nobody expected.

"The Purge 2" or "The Purge: Anarchy" has reportedly enjoyed the biggest opening for any horror film this year. It might be because of the twisted plot of the movie wherein normal people get to legally murder others once a year.

Watch "The Purge 2" full movie.

Here is the synopsis of the sequel, as published on IMDb:

A couple are driving home to their kids when their car runs out of gas just as the Purge commences. Meanwhile, a police sergeant goes out into the streets to get revenge on the man who killed his son, and a mother and daughter run from their home after assailants destroy it. The five people meet up as they attempt to survive the night in Los Angeles."

Why exactly is "The Purge: Anarchy" a surprising hit this summer? Jim Vejvoda of IGN gives his honest review of the sequel, saying:

"A marked improvement over its predecessor, The Purge: Anarchy is a scarier and more effective thriller that also features a solid central performance from Frank Grillo."

"The Purge: Anarchy is one of those rare sequels that's superior to the original film. It holds together better than the original Purge did, which became an exercise in histrionics during its homestretch. The sequel's characters are more compelling than the protagonists of the first film, and the viewer gets a much better sense of the effect The Purge has on the community as a whole than in the housebound original film."

Watch "The Purge 2" full movie in theaters today!