The 53-year-old Men in Black star takes on the role of Serena and Venus Williams' father Richard for the film, which tells the tale of how the famous sisters became the biggest superstars in the tennis world.
However, instead of the cinema-only release that most films would have received in a pre-Covid-19 world, this Warner Bros. flick will also be given a debut on HBO Max for 30 days, as is the case with all the movies the company plans to release in 2021.
According to The Hollywood Reporter, this prompted Smith to offer up some extra money to his co-stars and workers on the film as a reward for their hard work.
Speaking to Entertainment Tonight about his decision, Smith explained: "All I can do is my part, so it's always an honour and a pleasure for me to do my part, and everybody put in brilliant work. It was the COVID shutdowns, people really stuck with us."
He added: "It was a much more difficult process than anybody thought they were signing up for. I just felt that it was fair."
Smith is thought to have received around $40 million for the film, and used his own money to give a little extra to cast members like Saniyya Sidney - who plays Venus Williams - and Demi Singleton - who plays Serena - as well as other co-stars Tony Goldwyn, Jon Bernthal, and Aunjanue Ellis.
This isn't all that he's done, either.
According to one of his co-stars, Layla Crawford, who plays Serena and Venus' sister Lyndrea Price, Smith was handing out all sorts of gifts and treats whilst on set making the movie.
She said: "He gave us Polaroid cameras and different treats all the time. He's just such a generous and sweet person. He also gave us iPhone 12 Pro Max gifts in boxes.
"We ripped them open and everyone started crying. I literally cried my eyes out - it was the best gift ever. Will Smith is a blessing, I learned so much from working with him."
Goldwyn, who plays Paul Cohen, added: "What you said [he gave bonuses/gifts to all of the talent] is true.
"When this movie, when Warner Brothers decided not to release it, to put it out on streaming, there was a lot of controversy as people know and we just got a call from Will saying, 'I'm going to make this right.'
"I've never experienced it, I was floored. I just couldn't believe it."
If you want to catch the finished product for yourself, you can watch King Richard at cinemas around the UK from November 19.
Featured Image Credit: Warner Bros.
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