* This story may contain spoilers.
Lena Headey's Instagram account is under scrutiny after fans of Game of Thrones spotted an innocent-looking photo of a heart made from stones that might be a huge spoiler.
The English actress, 40, plays Cersei Lannister in the hit HBO series. But when she posted the image below with the caption "my stone heart", the rumour mill went into meltdown.
Those who have read George RR Martin's original A Song of Ice and Fire novels know that the symbol could be a not-so-subtle reference to forthcoming character Lady Stoneheart (a zombified Catelyn Stark).
Some fans believe that Lady Stoneheart will not feature at all this season but now, speculation is rife that viewers can expect to see her soon, possibly in the finale.
"Don't Google if you haven't read the books" one Instagram user wrote under Headey's picture. "Lady Stoneheart, confirmed" said another, while one fan wondered "if this counts as spoilers".
Headey's character was the subject of a recent controversial storyline in which she is raped by her twin brother Jamie in front of the corpse of her son, King Joffrey.
But Headey defended the dramatic scene, suggesting that Cersei eventually gave in to her sibling's advances in an attempt to feel something other than grief.
Martin also responded, insisting that while the sex is consensual in his book and the "whole dynamic" is different, it is up to the show's writers to convey it how they wish.