On 'Alexa Chung,' singer says opening up about Chris Brown is 'helping save lives.'By Jocelyn Vena Diane Sawyer and Rihanna Photo: ABC/ Ida Mae Astute "It's On With Alexa Chung" opened with the pop star telling viewers that "today's show is Rated R cause I'm talking over." The episode was an ode to the singer, featuring "America's Best Dance Crew" champs We Are Heroes dancing to a medley of Rihanna's songs and a fan makeover. Rihanna, wearing a black-and-red hooded sweatshirt and ankle boots, began by discussing her interview with Diane Sawyer, in which she opened up about the night that Chris Brown assaulted her.