Jane Pauley hosts this week's broadcast, which features Martha Teichner's interview with Dr. Mona Hanna-Attisha, the whistleblower who alerted Flint residents to the dangers posed by the very water they drank. Also: Anthony Mason catches up with country singer-songwriter Rory Feek; David Martin chats with investigative journalist Seymour Hersh; Tracy Smith checks out a tiny superhero with a big heart, "Ant-Man"'s Paul Rudd; Mo Rocca investigates why "dad wear" has become a fashion thing; and Scot Simon visits the one-ring Venardos Circus.