In 1955, NATO and the Allied Forces have been conducting secret, occult experiments in a bid to win the Arms Race.

[4] Simon Ball described the film as a 'fabulous piece of restrained retro Brit Sci Fi' that evoked the 'golden age of Brit Sci-fi when the government in Westminster could just throw National Servicemen at a threat whether an alien jelly monster (1955’s The Quatermass Xperiment, or X the Unknown 1957), a massive dinosaur (Gorgo, 1961) or an outrageously huge gorilla (Konga 1961)'.

[5] Mike McLelland stated that 'despite the obviously limited budget, some stiff acting, and various technical disappointments, The Rizen propels forward, maintaining interest with well-choreographed action, a suitably mysterious central plot, and a snazzy visual flair.

[7] Chris Luciantonio gave the film a less favourable review, commenting that 'even upon enduring the abysmal apocalyptic indolence of The Rizen for 140 incoherent minutes of dawdling about in underground corridors littered with feral mutants(?

[10] Sue Finn stated that 'with touches of the Cold War and '50s paranoia plus inter-dimensional portals', the film 'had the potential to be intriguing and involving, but is instead a wasted opportunity on the road to dullsville'.