What does it take to dive Titanic's sister ship? This huge vessel from a bygone golden age of ocean travel lies at over 100 metres (330') below the surface. It is not a dive for the faint-hearted. Requiring meticulous planning, precise execution and good conditions, only the most capable technical divers will ever experience it. Even then, tragically some do not make it back to the surface. Expedition Britannic is the story of the May 2019 mission to dive the Olympic-class liner-turned-hospital ship, HMHS Britannic. Sunk near the Greek island of Kea during World War I, she will only be ticked off the bucket list of relatively few of the most dedicated deep divers. Steeped in history, the opportunity to see a largely intact near-replica of the world's most famous ocean liner makes it an ultimate dive to aspire to. Deep wreck photography specialist Rick Ayrton is one such diver. Assisted by expedition leader Scott Roberts, he takes us through the planning, logistics and preparation essential for scaling one of the pinnacles of wreck diving. Then we explore the wreck with him - going deeper than most divers will in their lifetimes to photograph this once great ship - and make new discoveries.