There were many "giant-monster" films from the 50's . Some were terrible. Most were good, including this one. Yeah, if one were picky they could say the stop-motion effects (from King Kong effects man Willis O'Brien) are not as well done as Ray Harryhausen's or the pacing is a bit slow at times. For the most part, the actors do a credible job although Gene Evans (Dr. Karnes) overplays his part a bit. There is enough action to sustain interest and the story is pretty good (if not original). This monster just isn't in a talking mood! It's not only radioactive but has an electric charge that sends out the radiation. There is some decent stock footage as well. If you're a fan of 1950's sci-fi films, give this one a try.