Bill Travers puts in effort attempting to resemble Stephen Boyd while portraying "Ryan," who fronts a group of sailors eking out a living when an underwater tremor brings a massive reptile into their possession. They strike a bargain with "Dorkin" (Martin Benson) to showcase the creature in London, and then they’re on their way. It seems those involved hadn't encountered any “Godzilla” narratives, because it was predictable that eventually someone would recognize this as essentially a lesser version of “Gorgo.” The parent is bound to get impatient with calls for tea and ultimately start searching. The film gains something from the excessive use of clay animation and a very limited budget for effects, lighting, or sound—resulting in something unlikely to trouble Ray Harryhausen’s sleep. Nevertheless, it's a fairly diverting fantasy adventure that once again demonstrates how much damage the military inflicts on nearby landmarks compared to what these enormous, impervious monsters could ever achieve. The movie drags; it takes an excessive amount of time to build toward a conclusion that felt obvious from the very beginning. I did, however, find myself enjoying it—secretly.

Source on TMDB