In a report that I really hope proves to be false, and I'm sure they'll both deny it (which means nothing), Natalie Portman allegedly hooked up with Sean Penn at the Sunset Tower Hotel Bar in Los Angeles. Nevermind that she's only 27 and he's 48, oh, and also married. Star Magazine has the disturbing details...

...we report that the married actor — who had his wife Robin Wright Penn on his arm at the Academy Awards — was seen in a passionate embrace with Natalie Portman.

Following dinner at Sunset Tower Hotel's Tower Bar on March 17 — during which they were "constantly touching each other" — Sean, 48, and Natalie, 27, hooked up. (They previously served together on the jury at the Cannes Film Festival in 2008.)

"They went to a bank of elevators that only goes to the spa or to private rooms," an eyewitness tells Star. "They came back about 45 minutes later, and that's when I saw them making out."

"There's a door outside of the hotel's Tower Bar that has a bridge to the terrace, so it's semi-private," the eyewitness explains. "I used that path to get to the restroom, and when I came back, I had to go through some curtains — and that's when I interrupted Sean and Natalie! When they saw me, they were startled and quickly composed themselves."

Aside from the whole infidelity thing, it's hard to blame Sean Penn for trying (and possibly succeeding) to bang Natalie Portman. But what the hell is she thinking? Not sure if I buy this story just yet, although given Penn's past marital troubles it's not hard to imagine his involvement in this.