Law and Order SVU 18×13 “Genes” Season 18 Episode 13 Promo – An investigation hits a nerve with Benson (Mariska Hargitay) when a suspect claims his genetics causes him to commit rape. Also starring Kelli Giddish (Det. Amanda Rollins), Raúl Esparza (ADA Rafael Barba) and Peter Scanavino (Det. Sonny Carisi). Guest starring Greg Germann (Counselor Derek Strauss), Dalton Harrod (Will Stein), Emily Shaffer (Jessica Walcott), Michael Torpey (Nick Brown), Sean Patrick Reilly (Richard Witt), Jared Zirilli (Rodney Marsh) and Alex Hurt (Sam Dalton).