The infertile women who voluntarily underwent medical procedures to help scientists create the first test tube baby shouldered an intense personal cost.

That’s key to “Joy,” a fact-based British drama on Netflix Friday.

Bill Nighy and James Norton star as the two doctors who alongside nurse Jean Purdy ended a decade of trial and error in 1978 with the medical life-changing miracle of In Vitro Fertilization (IVF).

For New Zealand’s Thomasin McKenzie, Purdy offered an eye-opening exploration into a long-unsung heroine.

“I recognized the importance of the story and the care, research and artistry that went into writing the script,” McKenzie, 24, said in a Zoom interview from London.

“It was pretty clear this is something I’m really, really honored to be a part of.”

Purdy’s essential contributions had been obscured for 30 years. It wasn’t until a plaque was created in 2015 that confirmed Purdy as essential to the creation of IVF.

The procedure, a type of assisted reproductive technology, helps people or couples conceive by fertilizing eggs and sperm outside of the body.

“Joy” vividly shows the pain, suffering and trauma for women who could not conceive children. Marriages, lives were wrecked.

“Jack Thorne and Rachel Mason, the co-creators, did as much research as they possibly could. Painstaking research for years with the people involved in IVF and in the time during which this is set,” McKenzie said.

“On top of that, I did my own research to hopefully play Jean as accurately and as respectfully as I could.”

McKenzie mentions one story from Grace McDonald, the mother of the first boy born of IVF. “Grace had a beautiful relationship with Jean and really shone a light on who Jean was. The kindness, dedication and the loyalty that Jean had.

“But Jean was a very private person and it was very hard to find information about her. Because she went unacknowledged for so long, she had received very little attention. Also, she died really young at 39 and left no surviving relatives.

“Still, there was a huge effort in portraying her accurately.”

Purdy was a scientist and also an invaluable liaison between the women who volunteered their bodies for medical research and trials and the two physicians.

“That was a big part of the impact she made. She was involved in everything. Incredibly qualified, incredibly smart, she also took on the role of caring for the patients because she recognized that they needed to be acknowledged.

“That what they were giving was huge and was a great sacrifice, and that they needed to be brought together. IVF would have not happened, at least not in 1978, without her input.”

“Joy” streams on Netflix Nov. 22