At the Earth's Core (1976)

A huge burrowing machine tunnels out of control at ferocious speed, cutting clean through to the center of the earth, to the twilight world of pellucidar. Once there, Dr. Perry and David Innes are threatened by half human creatures, lizard-like birds, and man-eating plants.

Directed by: Kevin Connor

Starring: Doug McClure, Peter Cushing, Caroline Munro, Cy Grant, Godfrey James, Sean Lynch

Links: IMDb, Movie posters, Movie stills