Sometimes the greatest treasure lies just outside your comfort zone… A year after their underground adventure, Hugo, Alex and Julie are ready for another – this time underwater. At a scuba-diving camp in Croatia, the three friends search for a legendary Roman shipwreck and an emperor’s lost crown. Standing in their way is a ruthless businessman, his terrifying bodyguard and Hugo’s fear of swimming in the unpredictable sea. But sometimes the greatest treasure lies just outside your comfort zone…