Hayley and Arlene's volatile relationship exploded in the fall of 2000 when, after a boatload of people were drugged with the libido enhancing drug Libidozone, Hayley "killed" her mother. Hayley caught Arlene in bed with a drugged Mateo and strangled her. When her body disappeared from the deck – Adam had stumbled across the body and tossed it overboard – Hayley believed that Arlene was dead. Racked with guilt, Hayley developed an alternate personality, that one her mother. She paraded around town as her mother – complete with wig and tacky clothing.