 Gabrielle, Susan, and Lynette rush to the hospital in the middle of the night after receiving a phone call from Danielle telling them about Rex s heart attack. After not getting any better, the doctor suggests to Rex that maybe Bree was tampering with his medication. Rex writes her a note telling her that he understands, and then dies not knowing the real truth. Meanwhile, Lynette s marriage takes a dramatic turn after Tom, who quit his job under false pretenses due to Lynette s manipulation, vows that it is now her turn to go back to work and he ll be staying home with the kids. Carlos finally learns the truth about Gabrielle s affair with John, and he vows revenge as he is carted off to jail. A revenge-seeking Mike abducts Paul and takes him out to a deserted quarry, intending to shoot him after finding out that he and Mary Alice killed Deirde. Back on Whisteria Lane, the deranged Zach holds Susan hostage at Mike s house intending to kill Mike after learning from Felicia that he intents to kill his father. A series of flashbacks to the late Mary Alice Young s life and the true origins with Zach are finally revealed and exactly who killed Deidra. Also, Edie welcomes a mysterious new family to Whisteria Lane, the secretive Betty Applewhite and her teenage son Matthew.