HBO ruthlessly spoiled a huge Game of Thrones moment for Andy Samberg

It was the cost of working with Kit Harington

Andy Samberg has revealed that HBO carelessly spoiled one of the biggest Game of Thrones moments in the show's six-year history.

The comedic actor was set to work with Jon Snow actor Kit Harington on tennis mockumentary 7 Days In Hell when a member of HBO's PR team let the revelation slip.

"I learned it's a little bit dangerous to work with people from Game of Thrones, because... I'm a huge fan [and] I don't want spoilers," he explained to US chat show host Conan O'Brien. "But I Had a really major one blown for me because I was working with Kit."

He continued: "We got an email from the PR people at HBO and they were like 'hey, great news; we're going to run the first commercial for 7 Days In Hell after the Game of Thrones finale and there's going to be tons of excitement around it because Jon Snow dies."

Samberg, as you can imagine, was none too pleased; watch his reaction below.

The actor - who recently reunited with comedy trio Lonely Island for film Popstar: Never Stop Never Stopping - presented an Emmy Award alongside Harington who was nominated for Best Supporting Actor at Sunday night's ceremony. The HBO fantasy series went on to win in the Outstanding Drama Series category for the second year running.

Game of Thrones season 7 will be the penultimate series with the final batch of episodes due to arrive in 2018.