According to the National Enquirer, the "Die Hard" actor angrily confronted Ashton Kutcher during a hostile face-to-face meeting that left Kutcher trembling and begging Willis for mercy.
Here's what happens -- allegedly -- if you mess with John McClane:
"Ashton kept avoiding Bruce's calls and texts, but finally agreed to meet his wife's ex-husband at a private location," said a close pal of the couple.
"Bruce was livid! He reamed Ashton for his cheating — and humiliating not just ex-wife Demi, but his three daughters as well. He went at Ashton full force, giving him no time to make excuses for his embarrassing behavior, demanding that he get his act together FAST!
"Ashton finally broke down in tears, weeping uncontrollably as he begged for forgiveness."
The "Two and a Half Men" star — devastated because Demi's consulted a divorce attorney — begged Bruce to step in and stop her from committing to a separation.
He reportedly vowed to Bruce: "I will NEVER, EVER cheat again!"
Take this report with a grain of salt -- it is the Enquirer, after all! But let's not forget the sensational supermarket tabloid out-scooped more "respectable" media with the John Edwards scandal, so it gets things right, too. (We really want this epic Willis showdown to be true.)
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- Ashton Kutcher
- Bruce Willis