In a narrative that spans geography and time, from the Atlantic Ocean in the seventeenth century, to a correctional institute in Texas in the near future, and told from the perspectives of five very different characters, Speak considers what it means to be human, and what it means to be less than fully alive.

A young Puritan woman travels to the New World with her unwanted new husband. Alan Turing, the renowned mathematician and code breaker, writes letters to his best friend's mother. A Jewish refugee and professor of computer science struggles to reconnect with his increasingly detached wife. An isolated and traumatized young girl exchanges messages with an intelligent software program. A former Silicon Valley Wunderkind is imprisoned for creating illegal lifelike dolls.

Each of these characters is attempting to communicate across gaps--to estranged spouses, lost friends, future readers, or a computer program that may or may not understand them. In dazzling and electrifying prose, Louisa Hall explores how the chasm between computer and human--shrinking rapidly with today's technological advances--echoes the gaps that exist between ordinary people. Though each speaks from a distinct place and moment in time, all five characters share the need to express themselves while simultaneously wondering if they will ever be heard, or understood.