The main cast of Why Women Kill Season 2 includes:
- Allison Tolman as Alma Fillcot, a middle-aged housewife in 1949 who tries to join the local exclusive Elysian Park Garden Club.
- Lana Parrilla as Rita Castillo, the president of the club and a gold-digging wife.
- B.K. Cannon as Dee Fillcot, Alma's daughter.
- Jordane Christie as Vern Loomis, a private investigator.
- Matthew Daddario as Scooter, a struggling actor and Rita's lover.
- Verónica Falcón as Catherine Castillo, Rita's stepdaughter.
- Nick Frost as Bertram Fillcot, Alma's husband and a veterinarian.
- Rachel Bay Jones as Maisie.
- Daniel Zacapa as Carlo Castillo, Rita's elderly husband.
- Eileen Galindo as Isabel, Rita's maid and accomplice.
- Rondi Reed as Mrs. Carol Yost, the next-door neighbor.
- Virginia Williams as Grace, a member of the club.
- Jessica Phillips as Joan, another club member.
- Kerry O'Malley as Mavis, another club member.
- Cynthia Quiles as Brenda, another club member.
- Jack Davenport as The Narrator.
- Warren Kole as Detective Rohbin.
- Ryan McPartlin as Tom Madison.
- Andrew Leeds as Dr. Gibson.
This season is set in 1949 Los Angeles and revolves around the storyline of Alma Fillcot and Rita Castillo involving the garden club and a series of murders.
