Ah, the water: clear, blue, enveloping. And also cold and airless and deadly. Do we have any favourite films set on or under the water? You bet we do. From Moana’s beautiful vistas to Jaqueline Bisset’s effect on an impressionable eight year old, we look back at half a lifetime at sea in the cinema. Plus we reveal the secret to successfully pitching an ocean-going picture, and contemplate the benefits of drowning in butter.