Sheridan Smith is jumping in at the deep end for Paramount+ thriller The Castaways, starring as Lori, a holidaymaker stranded on a remote tropical island after surviving a plane crash.The drama reveals what happened to Lori after the crash and follows her sister Erin, played by Céline Buckens, as she tracks down her missing sibling in Fiji. Despite filming in Greece, Sheridan, 42, admits shooting The Castaways wasn’t much of a holiday thanks to her fear of water. “I was terrified of water and I’m in water for most of the show,” she says, laughing.