It's on of those films that works as a cheesy b-sci fi movie, which is better then it's
predecessor,  the  inept "Cube 2: Hypecube", and better then it has to be, but still pales in comparison to the still vastly superior "Cube", which remains one of my favourite films to date.
It's basic premise is the film is a prequel to the 1997 sci fi cult hit in which a guy, Wynn, who monitors the Cube (though who created the Cube is still unknown - it's hinted that it's possibly the government or aliens - personally I beleive it's both. The first half of the is dedicated to establishing a nice friend/worker between Wynn and his co-worker Haskell, and the scenes do have some well manage moments of comedy and drama.
However it's once Wynn enters the Cube this is where "Cube Zero" falters. Wynn's reason for entering the Cube is due to a woman having been placed there without a consent form (The observers are led to beleive that the subjects have signed consent forms and have basically choosen the Cube over execution) The characters inside the Cube albeit Cassandra - the woman he's become involved with, are shallow and recycled caricatures of the original Cube who pretty much before they are established.
Outside the Cube in the observation deck "Haskell" is met with a upper level official who appearently is credited a "Jax" a basic eccentric mad scientist who may have worked in another film, and has a few good one-liners, but here he's wasted.
Again, like "Hypercube", this resorts to dissorted flashback and introduces the concept that the monitors of the Cube can scan the subject's mind.
The ending, though slightly clever, is a direct word for word remake of another scene from "Cube". And though it offers some explanation, the acting is so poor it's overshadowed.
All in all it works as b-movie sci fi film, but as a sequel to "Cube" it fails.

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