"Avengers" star Dame Diana Rigg has shared how God "sent her back" to earth following a near death experience when her heart stopped after surgery.

Speaking to the Daily Telegraph, the 79-year-old actress revealed she was resuscitated by doctors when her heart stopped several months ago during a cardiac ablation, an operation to restore a normal heart rhythm.

"I had a heart operation two months ago; it was called a cardiac ablation," she recalled. "When I came round, the nurse said, 'You might find a bit of a burn mark on your chest.' That's where they jump-started me."

She continued," My heart had stopped ticking during the procedure, so I was up there and The Good Lord must have said, 'send the old bag down again, I'm not having her yet.'"

Assuring fans that she is "fine now," the actress, a devout Christian, said that the surgery made her "seriously ill" and prompted her to stop smoking.

"I got seriously ill; nothing but that would have made me stop," she said.

The Bafta, Emmy and Tony award winner, who played Olenna Tyrell in hit HBO show Game Of Thrones and now stars as Duchess of Buccleuch in ITV's Victoria, also said she believes her faith impacts her acting ability.

"I'm a practicing Christian, so maybe that's why I understand evil so well," she told the outlet. "It's a starting point, isn't it? I'm good at evil. Some actresses exude innate sweetness and goodness - I don't."

Rigg added, "I've got a darker side that I can call upon; and I understand the damage that some people do, wanting power and control over others, which is truly frightening."

Her faith also influences her charity work; ahead of the holiday season, she participated in readings at a Macmillan Christmas carol concert to raise funds for cancer research.

"I've been working with Macmillan for four years; I love carol concerts, and why wouldn't you support Macmillan? They're so wonderfully supportive to people suffering this terrible disease and they're in constant need of funds. Carol concerts are a wonderful way of fundraising," she said.

"There's so much need everywhere, the Macmillan event is the perfect way to give back," the actress added. "Just plug in to your beliefs and faith at this time of year - people tend only to do it at Christmas and Easter don't they? I'm not criticizing them, I'm much the same, and I love Christmas. It's a wonderfully communal thing, all of you bellowing out Come All Ye Faithful."