She cannot run. She cannot walk. She cannot even blink. As her batteries run down for the final time, all she can do is speak. Will you listen?

Speak is the story of artificial intelligence and of those who loved it, hated it and created it. Spanning geography and time, the novel takes us from Alan Turing's conviction in the 1950s to a Silicon Valley Wunderkind imprisoned in 2040 for creating illegally lifelike dolls. From a pilgrim girl writing her diary to a traumatised young girl exchanging messages with a software program, all these lives have shaped and changed a single artificial intelligence - MARY3. In Speak, she tells you their story, and her own. It is the last story she will ever tell, spoken both in celebration and also warning - a warning against creating and abandoning beings with the ability to feel as deeply as we do.

When machines learn to speak, who decides what it means to be human?