Stingray (1964)

S1E14 The Ghost of the Sea

Commander Shore is haunted by recurring nightmares from a traumatic sea battle five years prior, where he was left crippled after an encounter with an underwater vessel. During that harrowing experience, he was saved by an enigmatic figure whose identity remains a mystery. As the nightmares intensify, Shore grapples with his past, seeking to uncover the truth about his savior and confront the demons that continue to torment him.