John David Washington is ''still grasping'' his own movie, 'Tenet'.

The 36-year-old actor plays the role of the Protagonist in the Christopher Nolan directed movie - which also stars Robert Pattinson and Elizabeth Debicki - and whilst he did initially think he ''understood'' the film, he now realises that he doesn't know it all and is still working to understand it.

Speaking to GQ Hype about the movie, he said: ''I mean, literally on the first read, I thought I understood it, strangely. In my delirium, I thought I totally had, and I realised as the day went on, 'Ah, I don't have it at all.' But to answer your question directly, I'm still kind of grasping it.''

Meanwhile, John David previously revealed he wouldn't even tell his famous father - Denzel Washington - the plot of 'Tenet'.

He said: ''I would love to [tell Denzel], but I always feel he [Nolan] is looking at me. Like I've been bugged. Chris will know, it'll get out. I don't want to get waterboarded, so I always tell the truth, and I didn't say anything.''

However, John David revealed he and his parents, Denzel and Pauletta Washington, celebrated like he ''won the World Cup'' when he landed a role in the film and they were as excited as him when they found out he had secured a part in Nolan's latest movie.

The actor added: ''I was at my folks' place at the time, and we were just screaming at the top of our lungs, it was quite the spectacle. We were charging up and down the halls, flipping papers, anything we could get our hands on. We were so excited - it was like I won the World Cup.''

Even after John David secured the part, he had no idea what the movie was about until he was invited to Christopher's office to read the script.

He said: ''It took me about four hours. I'd read maybe 10 pages, go back five, read another 10, go back two ... I was playing classical music on my iPad to make me go slower, make me think I'm smarter. I tried everything - took my shoes and sweater off, did some stretches. I couldn't believe I was locked in his office reading this script nobody knows about.''