Director Giuliano Carmineo used to make spaghetti westerns with George Hilton but here he's in over his head completely with a flick lacking in all departments except maybe the one with the nudity which delivers plenty. Some better informed people say Rat Man is actually helmed by its more famous producer Fabrizio De Angelis, but it makes no difference as it's just cheap exploitation anyway, without any style whatsoever. A goofy piece of obvious crap, seemingly made only because the opportunity came knocking. You see, the little rat-guy of the title is played by Nelson de la Rosa, at the time of shooting the smallest man in the world. He looks hilarious, of course, like a little kid covered in dirt and blood and blessed with a set of fake teeth. The rest of the performances range from the pretty horrendous (whoever plays Dr. Olben) to the insignificant (Eva Grimaldi) and the all wasted (Janet Agren). But then there's always David Warbeck, God bless his soul. He always deliver with a smile on his face, though it sometimes seem like he's acting in another much funnier movie than the rest of the cast. Rat Man may be worth watching once if you like bad movies and peculiar monsters, but probably not if you don't.