Alfie Allen thought he'd been killed off at the end of 'Game of Thrones' season two.

Alfie Allen

Alfie Allen

The 32-year-old actor - who played Theon Greyjoy in the HBO fantasy drama series - was the subject of a prank from showrunners D.B. Weiss and David Benioff but he didn't realise and simply shot what he thought were his final scenes then left to go on holiday.

He explained on 'The Late, Late Show': "At the end of the season, there's a -- well, the script was given to me, and basically, I kind of give this rousing speech, if I may say so myself.

"So at the end of this speech, Bran [Isaac Hempstead-Wright] sort of pops out from somewhere and stabs me in the chest and says, 'This is my Winterfell, not yours.'

"And so I kind of just took it on the chin and got on with it, you know."

Eventually, other cast members urged the writers to come clean as it became clear the prank hadn't worked it.

He continued: "I think about three weeks past where I had kind of finished my shooting for that season, and people in the cast were kind of telling David and Dan -- because they had given me this fake script with this kind of fake ending -- that maybe you should tell him that it's fake."

Alfie was eventually told the truth because people felt he would be upset - but he wasn't.

'Late Late Show' host James Corden recapped: "So they wrote a script, telling you that your character would die as a prank, and because you went, 'Aw, okay,' it sort of backfired."

His guest replied: "I guess so, yeah, a little bit. So yeah, people decided to tell them that maybe you should call him, 'cause he might be tearing his hair out, but I wasn't, I was sunbathing."

The end of season two actually saw Theon betray the Stark family and pretend to kill Bran and Rickon in order to take Winterfell, and in later seasons Alfie's alter ego became the slave of Ramsay Bolton (Iwan Rheon) before trying atone for his past and rescuing Sansa Stark (Sophie Turner) from her evil husband Ramsay and ultimately losing his life in the final season while trying to protect Bran from the Night King.

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