International bestselling author Patricia Cornwell delivers pulse-pounding thrills in a series featuring a brilliant and unusual new heroine, cutting-edge cybertechnology, and stakes that are astronomically high

On the eve of a top secret space mission, Captain Calli Chase detects a tripped alarm in the tunnels deep below a NASA research center. A NASA pilot, quantum physicist, and cybercrime investigator, Calli knows that a looming blizzard and government shutdown could provide the perfect cover for sabotage, with deadly consequences.

As it turns out, the danger is worse than she thought. A spatter of dried blood, a missing security badge, a suspicious suicide-a series of disturbing clues point to Calli’s twin sister, Carme, who’s been MIA for days.

Desperate to halt the countdown to disaster and to clear her sister’s name, Captain Chase digs deep into her vast cyber security knowledge and her painful past, probing for answers to her twin’s erratic conduct. As time is running out, she realizes that failure means catastrophe - not just for the space program but for the safety of the whole nation.

Brilliantly crafted, gripping, and smart, Patricia Cornwell’s cliffhanger ending will keep readers wondering what’s next for Captain Calli Chase.

‘The creator of Medical Examiner Kay Scarpetta peers into space and finds just as much skullduggery there…introducing an equally strong, even more tormented heroine…in federal special agent Capt. Calli Chase.’ - Kirkus Reviews

‘Move over, Doctor Kay Scarpetta…Quantum inaugurates a new series with a confident new heroine…’ - The Telegraph

‘Cornwell’s long-time fans will recognise her talent for jumping immediately into action. From page one, the reader is drawn into the space and time of the characters, as Cornwell wastes no time getting the reader oriented into the story. The claustrophobic confines of the opening setting are fantastically described, to the point that readers may have to remind themselves to breathe normally.’ - The Nerd Daily

‘Brilliantly crafted, gripping, and smart…’ - Post Register

‘Buckle up for a race to the finish that does not disappoint.’ - Bookreporter

‘As always, Cornwell establishes time, place, and mood by expertly crafting each scene to make you feel as if you’re in it.’ -New York Journal of Books

‘Gripping, suspenseful, and leaves you wanting more.’ - Better Reading