Robert De Niro was nominated for an Oscar for his 1976 leading role in "Taxi Driver," about a Vietnam veteran working as a night-time cab driver in New York City to battle his insomnia.

Perhaps De Niro was so convincing in the role because he actually was a taxi driver.

While preparing for the film, De Niro obtained a cab driver’s license and reportedly worked 12-hour days as a cabby for a month to prep for the role. As Hollywood lore has it, he would even pick up passengers while on break during shooting around New York City. 

The Taxi and Limousine Commission tweeted a photo of the actor's real license, asking for stories from anyone who remembers riding in the back seat of his taxi:

You talkin’ to me? Anyone recall getting picked up by Robert De Niro while he researched his famous role in '76? #tbt pic.twitter.com/kn9szc4Yb3

— NYC Taxi & Limo (@nyctaxi) May 22, 2014

The license, which expired on May 31, 1976, even has a photo of a young De Niro, who was 32 at the time.

“Even 38 years later, the images of Robert De Niro as Travis Bickle in ‘Taxi Driver’ are still indelibly etched in people’s minds,” TLC Chair Meera Joshi told The Post’s Rebecca Harshbarger. “It’s very much to Mr. De Niro’s credit that he spent weeks behind the wheel of a real cab to get into character, and as we suggested in our recent tweet, if someone remembers hailing and riding with him, we hope they will share that experience with us.”

It wasn't the first (or last) time De Niro practiced method acting. For 1980's "Raging Bull," De Niro and co-star Joe Pesci lived and trained with each other before filming together. De Niro even gained a significant amount of weight to look more like his character and as a result, reportedly experienced difficultly breathing. 

In 1962's "Cape Fear," De Niro underwent a complete physical transformation, bulking up at the gym, getting tattoos, and reportedly having his teeth ground down.

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