Harry and Charlie are teenagers who meet at a time when gene-editing technology is starting to explode. Now, with a lab in the garage, anyone can beat cancer, enhance their brain to pass exams, or tweak a few genes for a year-round tan and perfect beach body.

But in the wrong hands gene-editing is the most deadly weapon in history. Killer T is a synthetic virus with a ninety per cent mortality rate, and the terrorists who created it want a billion dollars before they'll release an antidote...