Mission of Darkness is yet another run-of-the-mill tentacle hentai with average animation and laughable plot...with real shitty voice acting (don't you love it when they use "WE HAVE REAL PORN STARS VOICING THIS" as a SELLING POINT? Because porn stars are known for their STELLAR VOICE ACTING!) Dr. Ruba was a police scientist trying to figure out how all these girls are dying in strange ways, only for her to wind up getting it too.