Based on an incident that occurred off the coast of Florida in 1973, this film tells the story of four men who find themselves trapped in a mini-submarine in the ocean depths.
| Actor | Role |
|---|---|
 Lee J. CobbVictor Bateman | Victor Bateman |
 Martin BalsamT.C. Hollister | T.C. Hollister |
| JJoshua BryantSam Wallants | Sam Wallants |
 Paul Michael GlaserJack Beech | Jack Beech |
 Barra GrantGrace Wallants | Grace Wallants |
 Warren J. KemmerlingCmdr. Prestwick (as Warren Kemmerling) | Cmdr. Prestwick (as Warren Kemmerling) |
 Cliff PottsGordon Gaines | Gordon Gaines |
 Laurie PrangeChris Moffet | Chris Moffet |
 Phillip R. AllenLt. Cmdr. Hanratty | Lt. Cmdr. Hanratty |
 Redmond GleesonPO1 Stanton | PO1 Stanton |
 Roger KernJeff Turley | Jeff Turley |
 S. John LaunerCapt. Osborn | Capt. Osborn |
 Rod PerryJimmy | Jimmy |
| WWilliam WintersoleCmdr. Robbins | Cmdr. Robbins |
 Neil Brooks CunninghamDr. Lewison | Dr. Lewison |
 Fred FranklynHoward Wynter | Howard Wynter |
| NNorman HonathSailor #1 | Sailor #1 |
| AAndy KnightSailor #2 | Sailor #2 |
 Hunter von LeerSeaman Schrier | Seaman Schrier |
 Howard K. SmithNarrator (voice) | Narrator (voice) |