Rosalind Franklin and several of her colleagues and rivals step forward onto the stage to deliver, in a mix of choral address and rapidly shifting scene-setting, the story of the “race” to discover the structure of DNA in 1950s London. In January of 1951, X-ray crystallographer Rosalind Franklin—a Jewish British scientist in her mid-30s—arrives back in London after several years in Paris to work as a researcher at King’s College. Rosalind, however, is greeted with a rude awakening as she’s introduced to her colleague Maurice Wilkins—she has been brought to King’s to effectively serve as Maurice’s assistant as he works to uncover the structure of DNA. Rosalind is irate even as Wilkins urges her to think of their arrangement as a “partnership.”
As Rosalind and Wilkins begin working together, it becomes clear that there are many differences between them—personally, professionally, and ideologically. Wilkins refuses to take Rosalind seriously, and refers to her as “Rosy” or “Miss Franklin,” ignoring her title of “Doctor.” Rosalind’s research assistant, a graduate student named Ray Gosling, repeatedly attempts to diffuse the tensions between the two, but as Wilkins’ insults pile up, Rosalind is more and more resistant to his repeated attempts to apologize for his own verbal and behavior bungles and “begin again” on the right foot when it comes to their partnership. Rosalind and Wilkins occasionally have friendly conversations, such as when they discuss a production of The Winter’s Tale taking place in the West End, but ultimately Wilkins always manages to wind up leaving Rosalind feeling exploited and disrespected. Rosalind begins working in her own section of the laboratory and takes up a correspondence with an American PhD student in biophysics, Don Caspar, another Jewish person trying to make his way in a difficult field. As Rosalind and Gosling continue taking X-ray photographs of DNA crystals, Gosling tries to warn Rosalind to be careful around the machine, but Rosalind ignores his remarks and frequently steps directly into the X-ray beam.
After delivering a lecture on DNA at a conference in Naples, Wilkins is approached by a brash, cheerful young American scientist named James Watson. Watson asks to come study crystallography at King’s and help Wilkins win the “race” to discover the structure of DNA—but Wilkins insists there is no race. Watson approaches another scientist, a Cambridge researcher named Francis Crick, and the two begin working together relentlessly to make a model of DNA’s structure. As Wilkins returns to King’s College, having realized that other scientists are also trying to unlock the secret of DNA, he encourages Gosling and Rosalind to double down.
As Wilkins continues delivering lectures around Europe, Rosalind realizes he’s presenting the research they’ve done together as his own and becomes incensed. Tensions in the laboratory increase as Rosalind refuses to collaborate with—or even really speak to—Wilkins any longer. As Wilkins grows more and more frustrated with Rosalind’s coldness, he visits Crick and Watson at Cambridge and vents to them about how hard it is to work with her. Crick and Watson gleefully join Wilkins—in Cambridge and, later, at Rosalind’s own lectures in London—in making fun of Rosalind. When Crick and Watson cross a line, however, and hastily cobble together elements of Rosalind’s research to finish a poorly rendered, incorrect model, Wilkins grows suspicious of their methods. Back in London, Rosalind and Gosling develop a photograph they’ve recently taken with their X-ray camera and stare at the strange new image. They are looking at Photograph 51—the 51st image they’ve developed, and the first one that clearly shows a helical structure to DNA. Gosling is excited by the breakthrough, but Rosalind, who doesn’t believe in hastily publishing one’s results, insists on letting the image sit a while in her desk drawer before writing about it or presenting it to anyone—even Wilkins. Rosalind knows that as a female scientist—and a Jewish one—she “must never be wrong.” Later that night, Gosling takes the photo from Rosalind’s desk and delivers it to Wilkins, believing the man deserves to see the findings.
In January of 1953, Watson visits the lab at King’s College hoping to convince Rosalind to collaborate with him and Crick in the “race” they’re all running. Rosalind refuses, and Watson heads down the hall to visit Wilkins. Watson tells Wilkins that he deserves to work with collaborators who actually want to get along, work together, and publish their findings. Wilkins agrees and shows Watson Photograph 51, which he’s been puzzling over all morning. Watson, realizing what the photograph shows, rushes back to Cambridge where he and Crick begin developing a new model—a model they know will change their lives, and perhaps the entire world.
Don Caspar arrives at King’s to work alongside Rosalind, and Caspar is clearly attracted to her. Meanwhile, Wilkins visits Crick and Watson, and the two of them ask him if he’d be opposed to their trying to build another model—conveniently leaving out the fact that they’ve already started working on it. Wilkins says that if he’d known they were going to take another crack at a model, he wouldn’t have shown them Photograph 51. Nonetheless, they continue with their work. In February, Crick and Watson host Wilkins, Caspar, and Rosalind at Cambridge. Watson and Crick try to discern whether Rosalind is at work on her own model, but she does not volunteer any information.
Back in London, Rosalind continues her work—she grows exhausted, but she refuses to ask Wilkins for any help. Meanwhile, Watson and Crick, who are working together, complete their model. Rosalind falls ill one night at dinner with Caspar and subsequently learns that she has two large cancerous tumors—one in each ovary. Watson and Crick publish their findings—Watson is thrilled, but Crick admits that the prospect of fame is too much for him. Rosalind leaves the hospital and returns to the laboratory, determined to continue working. Wilkins tells her about Watson and Crick’s model and laments that he and Rosalind have lost the race, but Rosalind insists the opposite is true: the whole world, she says, has won. Rosalind laments that if she’d had more time, she might have been able to see what was right in front of her all along. Her self-pity leads her to question several other circumstances of her life, both within and beyond her control—but pulls herself out of her sadness and begins looking forward to continuing her work and attending a conference in Leeds the following month.
Before Rosalind can go to Leeds, however, she succumbs to her ovarian cancer and dies. The narrative of the play fractures as Wilkins steps forward out of the action and demands the whole thing “begin again.” He and Rosalind connect, suspended out of time and space, and Wilkins apologizes for not trying to meet Rosalind halfway. She, too, apologizes for her failure to collaborate with him. Rosalind and Wilkins share a sad, profound moment as they try to remember the name of the actress whose performance Rosalind loved in The Winter’s Tale—but can’t come up with anything and resign themselves to the notion that “she simply didn’t stand out.”