“Everyone who isn't us is an enemy.„~ Cersei to her son Joffrey Baratheon.

“When you play the game of thrones, you win or you die. There is no middle ground.„~ Cersei threatening Ned Stark about revealing the truth about her children, and her most famous quote.

“It was gloomy within the sept with the sky so grey outside. If the rain ever stopped, the sun would slant down through the hanging crystals to drape the corpse in rainbows. The Lord of Casterly Rock deserved rainbows. He had been a great man. I shall be greater, though. A thousand years from now, when the maesters write about this time, you shall be remembered only as Queen Cersei's sire.„~ Cersei's delusions of grandeur, thinking she will manage a great administration when she will become known as one of the worst and most short-lived.

Queen Cersei Lannister is one of the main antagonists of the A Song of Ice and Fire franchise and its television adaptation, Game of Thrones.

She is the current Queen Dowager of the Seven Kingdoms, the only daughter of Lord Tywin Lannister and Lady Joanna Lannister, the twin sister of Ser Jaime Lannister, and the older sister and archenemy of her younger brother, Tyrion Lannister. During the beginning of the story, she is the realm's Queen Consort, being the wife of King Robert I Baratheon, prior his death and the War of the Five Kings. She is also the former Queen Regent of the Seven Kingdoms, having ruled in her sons' stead until she was stripped of her position. She is the mother of her three children, Prince Joffrey, Princess Myrcella, and Prince Tommen, who are officially passed as King Robert's biological children and heirs, yet were all born out of adultery - which would become critical and one of the central causes of triggering the war.

Initially, Tywin had arranged for Cersei to be betrothed to Prince Rhaegar Targaryen and attempted to arrange their marriage, but resulted in failure due to The Mad King's paranoia. In the television series, she became the twentieth ruler of the Seven Kingdoms after her son, king and ruler-in-effect, Tommen I, who committed . With his death, she took over the Iron Throne and was officially recognized as the first queen regnant in the history of the Seven Kingdoms. Her reign, however, was short-lived, ending in King’s Landing where she met her death alongside Jaime.

Throughout the story, she is primarily the archenemy of the Houses Baratheon and Stark. In the last two seasons of the TV series, she also becomes the primary archenemy of House Targaryen.

In the television series, she was portrayed by Lena Headey, who also played Ma-Ma in Dredd, Morgana in Tales of Arcadia, Big Mama in Rise of the Teenage Mutant Ninja Turtles, and Aunt Grandma in Uncle Grandpa and Nell Williams as an adolescent. In the upcoming stage play, The Mad King, she will be portrayed by Daisy Franks.