London, 1923.

The academic world has its own secrets and rules. At a dinner party, one of the professor's wives is poisoned with an unknown poison; this daring crime excites the entire university. Dr. Maxwell becomes the main suspect.

But Saffron Everly, his student, does not believe in her mentor’s guilt. She decides to conduct her own investigation and find the real culprit. Neither the male professors nor the police take her seriously, because she is a woman. Saffron is looking for clues everywhere and, using her deep knowledge of botany, experiments with poisons.

She can’t cope alone, and fellow researcher Alexander, a mysterious young man who is hard not to get carried away, comes to the rescue. But the more secrets Saffron learns, the more dangerous her investigation becomes.

Who is the mysterious poisoner and why did he need it?