Margot Robbie says 'going dark' on screen is much easier

Margot Robbie finds it "easier to go dark" with her acting roles.

The 'Once Upon A Time In Hollywood' star admitted she slips into character "a lot quicker" when she can deliver a sad and emotionally charged performance, which meant playing a more cheerful take on the late Sharon Tate provided a real challenge.

Speaking during a live Q&A at Quentin Tarantino's New Beverly Cinema in Los Angeles over the weekend, she said: "I find it a lot easier to go dark, a lot easier to yell and scream and cry and do all that on screen.

"I feel like I can get there a lot quicker. But to be truly light all the time was actually hard -- weirdly hard. But a joy as well, kind of like being on this beautiful vacation all the time.

"And I worked with a movement coach a lot and did a lot of weird stuff: Run around and pretend to be a cloud! ... I looked like a lunatic."

The 29-year-old actress also found her own tactics to enhance her upbeat display on screen, as she tried to block out all negativity before she appeared on set.

She explained: "As silly as it might sound, I made a list of all the things that make me really happy, and then I would try and do all those things on the day that I was going to work or the day before.

"And all the things that gave me that downward pull in life, the stress and angst, I would kind of cut that out -- like, I couldn't look at emails within 24 hours of going to set."

Robbie will soon be seen embracing her darker side on screen again as Harley Quinn in DC Extended Universe movies 'Birds of Prey' and 'The Suicide Squad' in 2020.

The former will be the first movie in the DCEU with an R-rated certificate, and she hopes the rating will help dismiss any preconceptions people might have.

Robbie previously said: "I think there's a perception that a PG female-led action film is kind of considered a chick flick."