Critical Mass is a 2001 action film directed by Fred Olen Ray (credited as "Ed Raymond") and released direct-to-video.

It stars Treat Williams, Lori Loughlin, and Udo Kier.

[1] The film centers around a group of terrorists who take over a nuclear power plant and a security guard at the plant who tries to stop them.

Website Cool Target called it "enjoyable action nonsense" and stated: "Recycled footage to this extent is just lazy and kind of insulting but if you can get past this, Critical Mass is an enjoyably amusing low rent shoot-em up.

"[2] Moria.co gave the film only one star out of five, calling it "yet another version on Die Hard (1988) and the basic plot template it created of a lone individualistic hero inside a large building/facility single-handedly fending off a terrorist plot.