Gabrielle is a climate-change activist who shoots to fame when she becomes the first teenager to display a supernatural ability to grow plants from her skin. Hester is the millionaire daughter of an oil tycoon and the face of the family business. Theo comes from a long line of fishermen, but his parents are struggling to make ends meet. On the face of it, the three have very little in common. Yet when Hester and Theo join Gabrielle and legions of other teenagers around the world in developing the strange new 'Greenfingers' power, it becomes clear that to use their ability for good, they'll need to learn to work together.