“More specifically, do you think you could train them to do it?” Lawrence asked. “So far, only my male Ph.D. students have been able to operate the machines. You’d have to teach unskilled girls to produce results similar to those of Ph.D. students.”

Nora straightened to her full height. These…men…were just like the boys in the lab. They all believed they were superior in every way to girls and women. That was what this was about? She’d take that challenge and prove them all wrong.

“I know I could, and we’d get better results.” She hadn’t meant to say it so forcefully, but there it was.

“Is that right?” General Groves’s eyebrows rose nearly to his hairline.

“Yes, sir.”

“And if you’re wrong? You realize the war effort might hinge on your ability to deliver on that boast?”

“I’m certain…sir.”

Groves rocked back in his chair. “I like her pluck.” He turned to Lawrence and Oppenheimer. “If you’re wrong and she fails…”

“If we’re wrong—”

“Which we’re not—”

“We’ll chalk it up to her being a girl and replace her with a man,” Lawrence finished.

Groves steepled his fingers as he regarded her. Nora refused to wilt under the scrutiny. “Very well. We’ll do it your way.” He pointed at her. “You are sworn to secrecy. If you’re as smart as these geniuses seem to believe you are, I’m sure you’ve figured out the basic outline of what we’re attempting to accomplish. There are precious few people who know or understand the scope of this project. One wrong word uttered in the wrong company could spell doom for the Allies. Do you get my drift?”

“I do, sir. I promise you, I will not speak of it to anyone.”

“You couldn’t even tell your boyfriend.”

Nora blinked. “I don’t have one of those, sir.”

Groves smiled. “Good. You’re dismissed. You’ll be hearing from me when we’re ready to move on this.”

“Yes, sir. Thank you, sir. You won’t be sorry.”

“I’d better not be.”

She clicked the door shut behind her and made it to the bathroom on shaky legs. When she’d scoured every stall to be sure she was alone, she collapsed against the brick wall. Her hands shook. Three things were clear to her. Lawrence and Oppenheimer hand-picked her for this assignment. The assignment entailed separating uranium isotopes. The outcome of the war very well could depend on how well she did her job.

She would not fail.

“Samuel called for you, dear. Again.”

“Okay, Mother.” Mary took the stairs to her room two at a time.

“We haven’t seen much of him lately,” her mother called after her. “Why is that?”

“I’ve been busy studying. I’ve got that big English essay test coming up, remember?”