As it turns out, Marilyn Monroe pioneered the sex tape. (Courtesy Warner Bros.)

Now we all know Marilyn Monroe probably wasn't the most wholesome type — and now, it looks like she starred in a sex tape back in the 1950's.

The black-and-white 15 minute sex tape shows Monroe performing oral sex on a man whose face is out of the shot. Because he is never in the shot, it's probable that he knew the camera was there. Monroe never looks at the lens and it is not known whether or not she knew she was being filmed.

An illicit copy of the FBI-classified reel was just sold to a New York businessman for $1.5 million. A memorabilia collector, Keya Morgan, discovered the film while doing research for a documentary on Monroe and brokered its purchase.

If you're anticipating the release of the Marilyn Monroe sex tape on the web, don't get excited. The wealthy New York businessman who bought the footage wants to keep Monroe's sexy past buried (the jerk).

"He said he's just going to lock it up," Morgan said.

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