In a post that brought some fans to tears, Damian Lewis confirmed on Twitter that his beloved wife had sadly passed away after a battle with cancer.
"I'm heartbroken to announce that after a heroic battle with cancer, the beautiful and mighty woman that is Helen McCrory has died peacefully as home, surrounded by a wave of love from friends and family.
"She died as she lived. Fearlessly. God we love her and know how lucky we are to have had her in our lives. She blazed so brightly. Go now, Little One, into the air, and thank you," he said.
McCrory was best known for her portrayal of matriarch Polly Gray in hit BBC television series, Peaky Blinders and of Narcissa Malfoy from the Harry Potter movies.
Mayor of London, Sadiq Khan, described her as an "unparalleled talent".
"So sad to hear this news," said Mayor Khan.
"Helen McCrory was an unparalleled talent and made a difference to many young Londoners through her charity work.
"I have fond memories of her helping us unveil the statue of Millicent Fawcett in Parliament Square. Sending love to her family."
McCrory was born in London in 1968 where she went on to study drama at the Drama Centre.
In 2007 she and fellow actor, Damian Lewis (Band of Brothers and Billions) were married.
The couple had a daughter, Manon, and a son, Gulliver.
McCrory was appointed Officer of the Order of the British Empire (OBE) in the 2017 New Year Honours for services to drama.