A heavily disguised Robert De Niro spent a day at a homeless shelter in Boston, Massachusetts as he researched his new role in Being Flynn.
His make-under was so successful, the movie star had a full conversation with a regular at the shelter - about himself.
Director Paul Weitz explains, "We did spend time at Pine Street Inn homeless shelter, where Nick Flynn, who wrote the memoir, had worked. It was interesting to see him kind of blend into the woodwork, which he did very well.
"He had a cap pulled over his eyes and he pretended to have a cold so he could cover up his face.
"There was a very odd moment where somebody who worked at the shelter said, 'Oh, maybe Bob De Niro could play me!' He had heard something about how we were doing a movie and he did not realise that Bob De Niro was standing seven feet from him.
"Bob likes to play real people so he was trying to get a sense of the reality there. In the shelter he observed the people staying there and their body language wasn't downtrodden. They had erect posture and didn't want to appear to be marks and get robbed or beaten up so that's how he appears in the film."
De Niro also hit New York's Financial District in disguise to get a sense of what it was like to be an invisible homeless person in the busy Big Apple.
Weitz tells WENN, "I got a weather report that it was going to be snowing the next day and I called Bob up and said, 'How would you feel about getting into costume and trudging around the streets tomorrow if it snows?' So four weeks before shooting I went with him in a car and with a camera guy and we shot Bob walking around different neighbourhoods in his homeless gear.
"We chose different places where we hoped people would ignore a huge movie star. So we went down to the Financial District when everyone is arriving at work so they don't give a damn; they'd pretty much run anyone over to get to work."