Heath Ledger told Billy Bob Thornton to really hit him duringMonster's Ballfight

The actor stops by PeopleTV’s Couch Surfing to reminisce on that pivotal scene.

Watch the full episode ofCouch Surfingstreaming now onPeopleTV.com, or download the PeopleTV app on your favorite gadget.

One of the most pivotal scenes inMonsters Ballwas a lot more real than anyone may have realized.

That scene right there, I was really hitting Heath, Thornton says.

And he asked me to.

I said, Now listen, Im a little more of a veteran than you.

When I was a young actor I used to ask people to hit me and it hurts.

I said, Ill do it if you want me to, and he said, yo.

He said he needed it.

And I was hitting him pretty hard.

I did not stay in character all the time, the actor says.

That would have been really hard on a person.

Watch more in theCouch Surfingclip above.