‘Baby Reindeer’s Nava Mau chats with ET at the Gotham TV Awards in New York City. The actress reveals the cast ‘decided not to watch’ Fiona Harvey’s interview with Piers Morgan after internet sleuths accused her of being the ‘real-life Martha.’ Plus, Nava shares her approach to playing a character based on a real person, and recalls the cast’s reaction to the show’s popularity.