The 11-day voyage around the Baltic from Copenhagen to St Petersburg begins. Some guests are vying for the coveted prize of the most travelled passenger, an award given to diehard cruise superfans who have spent up to 7 or 8 years aboard.

The Captain is permitted to sail his vessel all the way into Stockholm through its stunning archipelago. But with thousands of islands to avoid and shallow waters, it is a terrifying task. If he gets it wrong, he could cause untold damage.

When turnaround day arrives, the crew must help 3,300 guests check out. They welcome a new batch with only a few hours to clean and prepare 1,800 passenger rooms.

New bridge officer Lauren faces tough tests; hotel engineer Scott lands a dirty job; Timothy must find some lost luggage.

The weather takes a turn for the worse, causing an emergency at sea and threatening to make one young British couple's wedding a washout.

Series following life aboard one of the world's largest luxury cruise liners on a summer season in the Mediterranean.