Scream Queens: Everyone Who Is Definitely in on the Killing

After being revealed as the hag of Shady Lane, Gigi's involvement has been shown through her suspicious phone calls to an outside party — probably whoever is doing the actual murdering. She has referenced a years-long revenge plot (because she's probably one of the sorority sisters who witnessed the sister's death in the '90s) and says they are cold-blooded killers, not kidnappers. She could be involved in some tangential way to the murders, but it's clear that Gigi is in deep.