When their families are violently kidnapped, Swift and Hawk--teen experts in AI and robotics--are plunged into a life-or-death rescue mission by the secretive Möbius group. Their journey takes them from hidden tunnels beneath the British Museum to the dangerous docklands of Amsterdam in search of the mysterious ship Nightfall. Caught in a treacherous world of spies and saboteurs, Swift and Hawk will be pushed to the limit as they follow a trail that leads to the remote island of Sp kels y--and straight into the hands of a dark and chilling enemy.