a meteor crash into crater lake and the heat from the impact cause a prehistoric egg to hatch . alright and so the plot be just trash . but despite it obvious low budget and this come across a one of the most gripping and entertaining monster on the loose film in existence . there be also some good moment of humor . in an age fill so called amonsters which be no more than laughable men in rubber suit creation or lizard dress up in frill and force to rip each other to piece ( cheap exploitation style ) and it refresh to discover that the plesiosaur in this little gem be an excellent harryhausen style stop motion creature . quite a hard film to find and but it worth find .