It's hard to believe that before the Star Trek films, it was the best way to get your dose of Spock.
And your dose of Bigfoot, Nessie, UFOs (well before X-Files), the Bermuda Triangle, Psychics, and on and on for 6 seasons.
Back then we didn't have the internet to read about forteana, conspiracies and ESP, so In Search Of... filled in for us.
I loved watching this show and Nemoy's voice over was perfect. Being born in1972, I still think of him as much for this show as for Star Trek.
These days, I still watch shows like Ghost Adventures, Dead Files and Haunted Collector, so I guess I've never really stopped searching.