Eric Roberts reveals Robin Williams pranked Julia Roberts with THIS prank during her first trip to New York

Eric Roberts, known for his role in Runaway Train, told a funny story about how Robin Williams played a prank on his sister Julia Roberts during her first visit to New York. In his new memoir Runaway Train: Or the Story of My Life So Far, Eric reveals the surprising moment that left Julia speechless and laughing.

The story takes place in Cafe Central, a famous New York cafe frequented by celebrities such as Cher, Al Pacino and Andy Warhol. Eric Roberts planned a clever prank to impress his younger sister, who was visiting him in the city. He enlisted the help of his famous friend Robin Williams, who was best known at the time for his role in Mork and Mindy.

Eric remembered telling Robin that his sister would be in town that week and they would have to freak her out about him. Williams quickly agreed and said, “Yeah, no problem. Okay.”

When the day came, Julia and Eric were sitting at a table eating hamburgers. Then Williams came along. He walked over, looked at her, opened the door, grabbed her hamburger and stormed out. Julia was surprised and screamed: “Was that Robin Williams?!”

Eric laughed and simply replied, “I think so, honey.” Julia's reaction was priceless: “He took my hamburger!” Eric Roberts called this a classic Robin Williams prank. He said this was Robin being Mork because he had already starred in the hit series Mork and Mindy, which was a perfect fit for his quirky mind.

Williams was known for his spontaneous and energetic personality and this prank reflected that side of him perfectly. Eric said he was thrilled to have impressed his sister in such a memorable way.

Years later, Julia Roberts and Robin Williams starred together in Steven Spielberg's “Hook” in 1991, with Williams playing Peter Pan and Julia playing Tinker Bell.

Beyond the prank, Eric Roberts' memoirs reveal more about his friendship with Robin Williams. The two actors were friends and Williams regularly advised Eric. He wrote that Robin constantly gave him advice. He also wrote that Williams was a little arrogant about his intelligence.

One memorable piece of advice came when Williams told Eric he needed to fight his arrogant demeanor. “You look arrogant, dude. People think you are,” Williams said.

“I know you're not, but people think you are, man, and you have to fight that.” Eric agreed with Williams, but noted that despite his true personality, that perception is hard to shake.

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