Squid Game has taken the world by storm since it landed on Netflix, with fans gripped by the gruesome thriller.
And one of its stars has revealed he had to suffer for his art, gaining a colossal amount of weight in preparation for their role.
Heo Sung-tae, who plays violent gangster Deok-su, looked back on the casting process for the show, explaining how he had lost weight during the pandemic.
But with his character being the hulking hardened criminal that he is, Heo needed to be fairly large, so had to put on over 15kg in just a month.
He told local media: "The projects I had planned were all postponed due to Covid-19. I lost weight while taking a break for five months but then I was contacted by the production team of Squid Game.
"When I met director Hwang Dong-hyuk, he asked me why I lost so much weight and told me that I had become so 'scrawny' when the physique of Deok-su is vital to the character.
"I gained 15 - 17 kg in one month. I think this is the first time I gained so much weight in such a short period of time."
And the actor said the sudden weight gain had a detrimental impact on his health.
He said: "My health became so bad because I gained so much weight in just a short time.
"The muscles on my calf tore and also my knees hurt. Overall, my health depleted. It doesn't matter about losing weight, but I think I have to carefully consider if I am given another role where I have to gain weight.
"I think gaining weight is three times harder than losing weight."
For those of you who aren't quite with it, Squid Game is a South Korean thriller which follows a down-on-their-luck group of strangers who agree to take part in a mysterious game with the promise of a huge cash prize.
The only catch is that those who are 'eliminated' during the series of sinister challenges are killed, quite brutally.
While fans have been full of praise for the show, Heo has been picked out for his brilliant performance.
Writing on Twitter, one fan said: "I would like to shed light on the incredible Heo Sung-tae. He deserves all the compliments and the hype.
"The fact that we ALL hate Deok-su, that we're scared of him and seeing how he is as a person, just SHOWS how talented he is. Show him love!"
While another chimed in: "I'm sorry Deok-su is my favourite and nothing in that show changed my mind."
Squid Game is available to watch on Netflix.
Featured Image Credit: Netflix