Macy admits he was amazed by his co-stars aptitude for alcohol during a night out in Cleveland, Ohio with Clooney and couldn't believe his eyes when the Ocean's Eleven star turned up for work the following morning looking great and no worse for wear.
He recalls, ""He came to do his bit; he was in it (film) for about four days... and he took us out that night and you can imagine this little bar was up for grabs and everyone wanted to buy George a drink.
""I watched him and he hammered back, I dunno, 12, 15 shots of tequila by the time I invited myself to go home and the next day the set was a mess, but George was fine... It was a lost day.""
But Macy's amazement was short-lived - one friend told him all about the star's bar secret.
He adds, ""Someone told me what George would do: somebody would say, 'George Clooney, I wanna buy you a drink,' and so he'd get the drink and he'd go, 'Hey' (bend over) and he would dump it on the ground and go like that (pretend to knock it back) - and nobody saw it.""