Mag claims that tunnels lead from Playboy Mansion to stars' homes, but is it just a prank?

Is Playboy pranking us? Thanks to April Fools' Day, we're not sure what to believe, so you may need to take this story with a grain of salt. Then again, it could be true ... what do you think?

We have a pretty good idea of what went on at the legendary Playboy Mansion, but you may not believe what went on under it, INSIDE EDITION reports.

Playboy magazine reports it has just discovered blueprints for a network of tunnels beneath the mansion that supposedly led to the homes of Jack Nicholson, Warren Beatty, James Caan, and Kirk Douglas!

Now, dig this, a photo from the late seventies allegedly shows an excavation in progress beneath the mansion!

And one shows the newly-discovered tunnel plans, check out the bunny logo on the plywood wall!

In the blueprint, it says the tunnels lead to James Caan's house, Nicholson's home, one to Douglas', while and another one goes all the way to Warren Beatty's house!

Former Playboy bunny Izabella St. James dated Playboy founder Hugh Hefner and wrote the book Bunny Tales: Behind Closed Doors at the Playboy Mansion.

She told INSIDE EDITION, "I think there may be some truth to it. I heard something about tunnels when I lived there one time. I always thought it was Playboy folklore, urban legend."

One Playboy source is saying the tunnels were closed up in 1989.

None of the four actors named has commented on the story. Back in the day, all four actors were known to frequently visit the Playboy mansion.

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