After King Joffrey’s (Jack Gleeson) death at the reception of his wedding to Lady Margaery Tyrell (Natalie Dormer) in Game of Thrones, the killer was a mystery to those who hadn’t read George R. R. Martin’s Song of Ice and Fire. In "Oathkeeper," the mystery is solved.

Lady Olenna Killed Joffrey

Lady Olenna Tyrell (Diana Rigg), the grandmother of Joffrey’s wife of a few hours, is the one who committed the final act of murder. She admits her guilt to Margaery before leaving King’s Landing for Highgarden while giving her advice about how to use her skills as the wife of a king – more specifically to the young and impressionable Tommen – to thrive and use her will.

Though Olenna is technically the killer, she didn’t commit regicide without help. Petyr Baelish (Aiden Gillen) was the brains of the operation. He had a necklace made in which one of the stones was laced with poison and had Ser Dontos gift Sansa (Sophie Turner) with the necklace as a token of his affection for her. Then, Olena, while adjusting Sansa’s necklace at the Purple Wedding, was to pluck out the tainted stone and subsequently drop it into Joffrey’s wine cup.

Explaining his motives to Sansa, Petyr offers a wordy explanation about the need of doing unexpected things to keep your enemies constantly guessing and perpetually confused. Furthermore, it provided a distraction so that he could take her with him to the Eyrie, where he plans to marry her Aunt Lysa. Petyr is hungry for more power.

As for Olenna, her reasons for wanting Joffrey dead were simple. As she told Margaery, she couldn’t have her marrying a monster such as Joffrey. There’s also the reality that Tommen will prove to be a more malleable king for Margaery to manipulate to best serve Highgarden.

– Chelsea Regan

For More Game of Thrones News:

> 'Game Of Thrones' Recap: Dany Takes Mereen; Littlefinger Tells Sansa His Plans; Bran Is Captured

> 'Game Of Thrones' Recap: Littlefinger & Sansa Reunite; Tywin Takes Control In King's Landing

> 'Game Of Thrones' Spoilers: 'Breaker Of Chains' Episode Will Be A Game-Changer

> Peter Dinklage & Rosalie Thomas Get Real On The Set Of 'Taxi'

> Game Of Thrones: Who Killed King Joffrey Baratheon?

Read more about: