Robert S. Bader and Dick Cavett‘s Groucho & Cavett (PBS American Masters, 12.27) was shown yesterday or the day before at the Hamptons Int’l Film Festival.

Excerpt: “Cavett, a writer for Jack Parr on The Tonight Show, met Marx at the funeral of playwright George S. Kaufman in 1961. When Cavett made the transition from writer to comedian in 1965, he was encouraged and mentored by Marx. In 1968, Cavett became the host of his own talk show and Marx became a frequent guest, capturing what Cavett calls ‘the last of Groucho’s greatness.’

“Groucho & Cavett chronicles the pair’s relationship through new interviews with Cavett, footage from Marx’s visits to The Dick Cavett Show and other rare recordings.”

I’ve always heard about Groucho’s off-color and in some cases delightfully vulgar sense of humor, which he only shared in private or during commercial breaks on talk shows. Why do I have this feeling that Groucho & Cavett, obliged to defer to PBS decorum and gentility, won’t share any of this?