Stingray - Season 1 (1986)

Ray is hired by an elementary school teacher to find her husband. He infiltrates a marine research facility where the man had been working as a diver.

Ray is picked up by the police and brought to the Chief who tells him he knows about him and what he does. Instead of arresting him before, he chose to sit on it till he could use him and it appears the time is now. It seems the man's wife was killed and it appears they were not happily married so they're turning their attention towards him. He's hoping another cop who was with him when his wife was killed will back him up but the cop not only doesn't, he passes the lie detector test. So with a girl who's a friend of the Chief he tries to prove his innocence.

When a young woman tries to kill Ray, and then steps in front of a bus, his investigation leads him back to a University research program where several students have committed suicide. It turns out the program is being run by a man related to Ray's mysterious past.

Ray is contacted by a doctor at a mental hospital about some strange occurrences. But, once he gets inside the hospital, he finds out the "doctor" is really a patient. However, there really are some nefarious activities that he uncovers.

An employee of WHO shows up at Ray's door, and promptly dies after telling Ray he's infected with smallpox. Ray's investigation leads him to a secret government research facility.

Ray is hired by Sister Allison of a traveling religious show to find a serial killer murdering prostitutes in the cities that the show stops at. Ray goes undercover as a preacher to find the culprit, but when he does it seems to profoundly affect him.