A fast-paced, action-adventure thriller for readers of The Martian.

'Charlotte Robinson is a story genius!' - Naomi Alderman, author of The Power

ONE SMALL STEP. ONE FATAL MISTAKE.

On the barren plains of the Kazakh Steppe, Alyssa Wright stands on the brink of the most ambitious space flight in history: a one-way mission to Mars. But when disaster strikes, she begins to uncover a conspiracy that threatens her life - and the lives of everyone on board.

In Hong Kong, a coder vanishes from his home, leaving nothing behind but a cryptic warning and his cat. Pursued by violent forces, his sister finds herself on the run, in possession of the one thing capable of saving him.

Amidst a dark vacuum of nothingness, as the Argo spaceship hurtles toward Mars, the crew realise that someone is sabotaging the mission from the inside. Every second brings them closer to catastrophe, and time is running out.

Across Earth and space, three stories collide in a breathless thriller that asks: what is the price of progress, and who must pay it?