A call to oceanographer Edie Widder about a fish with a very odd immune system quickly becomes something else: a dive into the deep sea, into a world of brilliant light. But down there, the light doesn’t behave like light—it sparkles and glows, but also drips, squirts, and dribbles. Today, find out how creatures make the light and how they use it, from hunting and hiding to maybe even … talking, and hear about a series of mysterious moments where Edie goes from studying the creatures to becoming one of them.