<P> In the pilot episode, Mary Alice introduces herself as the stereotypical American housewife to husband Paul Young (Mark Moses) and son Zach (Cody Kasch). On one Thursday, she proceeds to go to her hall closet to retrieve a revolver, and shoot herself in the head with it . </P> <P> Paul asks Mary Alice's neighbors and friends, Susan (Teri Hatcher), Lynette (Felicity Huffman), Bree (Marcia Cross) and Gabrielle (Eva Longoria), to go through her clothes and other belongings and then pack them up, as he thinks it will be too hard for him . The women end up finding a letter addressed to Mary Alice, a blackmail note reading, "I know what you did, it makes me sick, I'm going to tell ." Thereafter, the women make a series of discoveries concerning Mary Alice's past and her possible motives for ending her life; she was being treated by Dr. Albert Goldfine (Sam Lloyd) where she revealed that she once went by the name Angela, and she may have had something to do with a baby that went missing . Paul soon discovers who sent Mary Alice the note, their next - door neighbor struggling with financial difficulty, Martha Huber (Christine Estabrook), whom he ends up strangling to death out of pure rage and burying her body in the nearby forest . Meanwhile, her son Zach begins having flashbacks and is under the impression he killed a baby named Dana, who he believed to be his younger sister and reveals this to Julie Mayer (Andrea Bowen), Susan's daughter . Paul worries over what Susan is spreading about their family, so he tells Susan in private that Zach accidentally killed his younger sister, Dana, and that he and Mary Alice covered it up to protect him . However, it becomes evident that this is not the case when Paul tells Zach that Dana is still very much alive . </P> <P> Felicia Tilman (Harriet Sansom Harris), Martha's sister, soon arrives on Wisteria Lane to find out what happened to her sister . While inside Paul and Mary Alice's house, she recognizes a picture of Mary Alice and claims her to be Angela, a nurse she worked with years prior in Utah, but Paul is adamant that she is mistaken . Felicia, however, knows that Mary Alice was in fact Angela and later tells Zach that she knew him when he was a baby, and that his original name was so lovely: Dana . In the first - season finale, the mystery behind Mary Alice's suicide is revealed in full . In March 1990, Todd and Angela Forrest could not conceive and one night a woman named Deirdre Taylor (Jolie Jenkins), a heroin addict whom Angela had treated at the rehabilitation hospital where she worked as a nurse, came to their house looking for money and offered to sell her son to them, to which they eventually agreed . When Deirdre returned to the hospital as a patient soon after and suspicion arose as to where her child was, Angela knew they had to leave town . They moved to Fairview and bought a house on Wisteria Lane, changing their names to Paul, Mary Alice and Zach Young . In 1993, however, Deirdre came to their home, seemingly sober, demanding that she reclaim her son . After a verbal fight, Deirdre went to take her child, when Mary Alice stabbed and killed her . Zach woke up and saw the body, which led to years of his parents brushing off his memories of that night as nothing . Paul and Mary Alice dismembered Deirdre's body, put it in a toy chest and buried it under their pool . Years later, Martha recognized Mary Alice in a group photo in Felicia's house, leading to Felicia to tell Martha about how Angela and Todd possibly disappeared with Deirdre's child and hopefully gave Dana a proper home . Martha then blackmailed Mary Alice and she, in desperation, committed suicide . </P> <P> Mary Alice appears in flashbacks and dream sequences in the remainder of the series, during which several previously unknown details about the day she committed suicide are revealed . In season two, Mary Alice was the first of the housewives to move onto Wisteria Lane, to which she recounts how she met each of them and how they all became friends . In season three, Lynette has a recurring nightmare of the last time she spoke to Mary Alice; while she was reading her blackmail note for the first time on her front lawn, the day she committed suicide . Lynette asks if she is okay, to which Mary Alice says she is and while Lynette knew otherwise, she had groceries that needed refrigeration, so she simply told Mary Alice she would see her later . After a hostage situation at the local grocery store, Lynette has one final dream in which she speaks to Mary Alice and asks how she can help her; she tells her that we can't prevent what we can't predict, and to enjoy the beautiful day, as we get so few of them . Afterward, Mary Alice states that this was the last time Lynette would ever dream of her, and for her sake, she is grateful . In season four, Mary Alice appears in two separate flashbacks to when Katherine Mayfair (Dana Delany) was first living on Wisteria Lane; in "Now You Know", she and Susan knock on Katherine's door wondering why there is a moving truck outside her house, to which a rattled Katherine says she got a new job in Chicago . In "Free", Mary Alice is shown to have been babysitting Katherine's daughter Dylan (Hailee Denham) the night the child's father returned, to which Katherine looks immediately panicked and Mary Alice apologizes for any wrongdoing . </P>

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