Gorgo

A volcanic eruption brings to the surface a 65-foot prehistoric monster. Two treasure divers capture the creature and take it to London as the star attraction at a circus. A scientist points out that the creature is only an infant, and a full-grown specimen would be over 200–feet in height. Sure enough, Gorgo’s mother comes thundering ashore, ready to reclaim her offspring but not before she pulverizes generous portions of London!