Excited fans packed the courtroom where the actor was due to testify against defendants accused of exploiting his name to promote a fashion brand
The Hollywood actor stayed as cool as one of the characters in his movies, making several quips during 90 minutes on the witness stand
He spoke through an interpreter, apologising for his lack of fluency and throwing in the occasional word in Italian
It's a long time since a fraud trial has provoked this much interest.
Crowds thronged around a tiny Milan courtroom, mobiles in hand, hoping to get a snap of the main witness.
And at one point the judge was forced to halt proceedings and have a woman escorted from the building.
Extraordinary scenes, perhaps, but not when you consider that this was a court action in which George Clooney was in the witness box.
The actor – who owns a holiday home in nearby Lake Como – had been called to testify against three defendants charged with fraudulently using his name to launch a fashion line.
Keeping his cool amid the hoopla, the Ocean's Eleven star fired off a volley of his trademark quips during his appearance.
Making his way through the melee, wearing a navy blue suit with a crisp white shirt, George joked with fans: "Don't crush my lawyers".
One of the accused had turned up for the proceedings.
"This is the first time I've ever seen him," the Hollywood talent said, comparing the defendant to his likeness in a photo that he'd been given on the stand.
Then with just a trace of irony, the 49-year-old added: "So I'd like to say hello, nice to meet you."
At the heart of the evidence was a series of pictures showing him with the defendants, which George claimed, were doctored.
Examining one picture he explained: "Here, for instance. I don't smoke and I don't wear that watch".
Then after a pause he added: "I also don't wear long jean shorts."
On a more serious note that star told the court: "I am here because I believe in justice".
"I am here to speak because some people are trying to use my name to gain advantage not over me but of others".
At the end of the 90-minute session Judge Pietro Caccialanza thanked the star witness, wryly noting that the session "has lasted as long as a movie".