LAND UNKNOWN 1957 (UNIVERSAL)

Jock Mahoney stars as one of several people who, during an antarctica expidition crash in a warm weather area several thousand feet below sea level and fight for survival against prehistoric monsters.
The monsters are pretty cool for the day and the cast does a very good job making it seem real.
Shawn Smith is the female reporter who goes with the men and William Reynolds and Phil Harvey are the other crew members. Henry Brandon is a "caveman" they encounter and he turns out to be a man who expidition was lost ten years before. Finally we have Douglas Kennedy as the man who put the entire trip together and he stays on the main ship and attempts to find the crew.
Good Universal monster movie here with plenty to please every fan of the genre.