Season 15 Episode 20 (Beast's Obsession) in 2014 Main Cast: Mariska Hargitay as Dectetive Olivia Benson Danny Pino as Dectetive Nicolas "Nick" Amaro Jr Kelli Giddish as Dectetive Amanda Rollins Ice-T as Dectetive Odafin "Fin" Tutuola Raúl Esparza as ADA Rafael Barba Special Guest Start: Pablo Schreiber as William Lewis Donal Logue as Lieutenant Declan Murphy