In episode one, in Liverpool on the River Mersey, a crewman tragically passes away while attempting to board a tugboat while jumping off a jetty. The MCA's Regulatory Compliance Investigations Team look into the incident to investigate how something like this could have happened. The investigator heads back to the scene of the incident and gathers as much evidence and intelligence as possible before taking it to a jury. If prosecuted the owners of the tugboat could face a massive fine or even a prison sentence.Over in the North Sea, a mayday call is picked up from a fishing trawler in serious trouble. The crew at Sumburgh Search and Rescue head over to the location to find the vessel has sunken and the sister boat is trying to rescue the floating fisherman in treacherous weather. In one of the most dramatic incidents in recent memory, it's a race against time to rescue the helpless crew as they battle the rising swells and powerful gale force winds.At the Joint Rescue Coordination Centre in Fareham, a mayday call from an elderly walker as he's ended up stuck in the mud. This quickly turns into a risky life-threatening operation involving the Coastguard Rescue Teams and a Search and Rescue Helicopter. Fighting time and the deteriorating cold weather, the anxiety builds to see if the teams can find, access and extract the casualty, before it's too late.Meanwhile, the Fixed Wing Plane is out monitoring the sea from above when they come across crew members on a fishing trawler not wearing life jackets. This is fed back to HQ and an inspection of the vessel takes place to check all is well on board and to inform the crew of the flight's findings.