A party of tourists -- including a state senator, a park ranger who was her one-time lover, a cantankerous professor, and an escaped convict -- are trapped deep inside the caverns of an unnamed national park, rescued briefly, and then caught in a second cave-in.

• Irwin Allen Productions
• Warner Bros. Television
• Dennis Cole
• Susan Sullivan
• Leslie Nielsen
• Ray Milland
• Julie Sommars
• Sheila Larken
• Lonny Chapman
• James Olson