Hollywood actor Gary Oldman, whose streaming series ‘Slow Horses’ returned for a third season last month, critiqued his performance as Sirius Black in the ‘Harry Potter’ franchise on the latest episode of Josh Horowitz's ‘Happy Sad Confused’ podcast.

Gary Oldman, 65, thinks his portrayal of the beloved Harry Potter character was "mediocre”, reports People magazine.

After telling Horowitz, “I think my work is mediocre in it,” the Oscar winner said he believes he could have performed the role "differently”.

As per People, his approach may have been different if he had read J.K. Rowling's original books before starring in the films, as his late co-star, Alan Rickman, said. “Maybe if I had read the books like Alan, if I had got ahead of the curve, if I had known what's coming, I honestly think I would have played it differently," Gary said on the podcast.

The actor joined the franchise as Sirius Black in 2004's ‘Harry Potter and the Prisoner of Azkaban’ and reprised the role in ‘Harry Potter and the Order of the Phoenix’. He also had a cameo in the franchise’s final film, ‘Harry Potter and the Deathly Hallows: Part 2’.

Oldman said he typically critiques his past performances. "It's like anything, if I sat and watched myself in something and said, 'My god, I'm amazing,' that would be a very sad day,” explained Oldman. “Because you want to make the next thing better.”

While the actor isn’t a fan of his performance, he recently shared how appreciative he is of the franchise. Earlier this month, Oldman told Drew Barrymore in an interview on her eponymous talk show that the ‘Harry Potter’ franchise and Christopher Nolan’s ‘Dark Knight’ trilogy helped his personal life.

Oldman explained to Barrymore, 48, that he had turned down opportunities in order to spend time with his children Alfie, 35, Charlie John, 24, and Gulliver Flynn, 26, after becoming a single father in 2000.