This is the penultimate episode of DI Humphrey Goodman (Kris Marshall, who I first saw in Love Actually) and we are also introduced to his replacement DI Jack Mooney (Irish actor Ardal O'Hanlon) in a kind of a cross-over. Marshall and his family embraced life on the island where Death in Paradise was filmed, but thankfully he managed to continue in Beyond Paradise a few years later. One difference is that a Death in Paradise season typically has eight episodes, whereas Beyond Paradise has six. Anyway, here there's a man overboard, and Goodman has to resolve it quick fast, as this is his penultimate episode sadly.