The original series was hosted for most of its run by the late Garry Moore who also had his own variety show that was instrumental in giving Carol Burnett's career a huge boost.
The panelists during the years I watched were former Miss America Bess Myerson, game show host Bill Cullen, comedian Henry Morgan, and actress Betsy Palmer.
The original and most famous version of I've Got A Secret aired on CBS from 1952 to 1967. The show was briefly revived in the 70s and there was even a cable version of it on Oxygen in 2000 - 2001. Until now I hadn't thought about it in many, many years.
In this episode from March 30, 1964 former Beatle Pete Best is one of the guests. There are some things you should notice while viewing his brief appearance. Moore feigns surprise when Pete tells him his secret. A bigger lie comes from Best when the host asked him why he left The Beatles. The drummer's explanation was total fabrication. He was devastated when The Beatles fired him. Also, I was totally surprised when Moore announced that Best still had a social relationship with the Fab Four. In these very early days of Beatlemania in America I'm guessing the real story wasn't common knowledge yet.
Also, in what is typical of the day, notice how quickly the conversation turned to The Beatles' hairstyles. Both Myerson and the crew-cutted Cullen bring the topic up immediately during their turns and later Moore, whose hair is the twin brother of Cullen's, does the same. Before they became permanently embedded as musical and cultural icons it was the group's carefully coiffed hair that was often the most discussed thing about them.