The "Pulp Fiction" star was only 20 when she read for a part opposite "The Irishman" actor in the 1993 comedy/drama film "Mad Dog and Glory", but she did something ballsy at the try-out, which really grabbed the casting director's eye.
"In the audition the character is trying to get through a door and he's (De Niro) not letting her get through the door," Uma explained during an appearance on "Live with Kelly and Ryan".
"So finally, I just shoved him. And that's why I got the part - I was the only one who would shove him. (I thought,) 'Gotta get through the door so get outta the way.' Because no one would do that."
Uma still can't believe she was brave enough to get physical with the acting icon, because she felt "completely intimidated" by him, but the experience of making "Mad Dog and Glory" was one she'll never forget.
"He was... one of the most impactful people I worked with when I was really young," she adds.
And best of all, she has teamed up with the movie legend again in new movie "The War with Grandpa".
"I play his daughter," the actress said. "He doesn't want to be alone so she moves him in with their family and he takes over the room of his grandson - and that's the war."
Thurman is much less scared of Robert these days, now she's a movie star herself, adding, "It was wonderful to work with him again."