Red sky at night, sailor's delight. After their mission in London, Nomad, Riff, Phoenix and Orbit are back at HELIX, training to master their magic. But things have changed. Nomad's secret is out. Her peers know she is a Witness; a sorcerer with the rare ability to read others' magic. This causes ripples at HQ, especially when it means that Steel, the most popular cadet in her class, is no longer the centre of attention. But there are greater threats than new rivals. When the cadets are sent to New Zealand to investigate a top-secret case, they find themselves in more danger than they bargained for. With no one to trust and time running out, it's a race to stop the Inductors before they have enough power to destroy HELIX for good. Red sky at morning, sailor's warning . . .