Edie organizes a neighborhood search for Mrs. Huber, just as her sister arrives on Wisteria Lane; Bree agrees to a separation and asks an attractive pharmacist on a date; Susan's ex-husband, Karl, suddenly returns for a visit; Lynette's fears Tom is attracted to their nanny.
The residents of Wisteria Lane learn the fate of Martha Huber; Susan confesses to Edie about her role in her house fire; Bree finds George getting a little too close for comfort; Carlos is released on bail, and placed under house arrest.
When Tom's father visits, Lynette unwittingly learns a family secret; Susan is disturbed by Julie's growing romance with Zach; Rex attempts to reconcile with Bree as she tries to play hard-to-get; Gabrielle is shocked when John's parents demand her help.
Susan looks forward to a romantic date with Mike until she learns a surprising fact; Lynette's neighbor accuses her twins of thievery; Bree learns of Rex's sexual needs; Gabrielle's work adventures continue.
Mike is questioned in Mrs. Huber's murder; John's friend Justin tries to blackmail Gabrielle with his knowledge of the affair; Tom wants a big promotion, but Lynette fears she would be left alone with the kids even more: Julie learns of Zack's dark side at his pool party.
Maisy Gibbons' series of unfortunate events shocks Wisteria Lane; Gabrielle and Carlos' sewer system goes out; Lynette learns of a rumour that her twins started a head lice epidemic; Susan finds a surprising ally after her breakup with Mike.
Mama Solis' awakens from her coma, as Gabrielle and Carlos fret over their financial issues; Lynette befriends a deaf woman; Bree encounters more trouble when disciplining Andrew; Susan finds herself attracted to Edie's hunky new contractor.
Susan's mother pays an unexpected after breaking up with her boyfriend; Gabrielle faces Carlos' wrath after he learns about the hospital settlement; While babysitting Lynette's children, Bree decides to punish the twins for misbehaving; Felicia gets closer to Zach where he reveals to her more disturbing details about his family.
Lynette learns that no good deed goes unpunished when she befriends Mrs. McClusky; Susan's mother decides to try to jump-start her and her daughter's love lives; Bree forces Andrew to talk to the family priest about his conflicted sexuality.
Gabrielle plans a big party to bid farewell to Carlos and begins to suspect she's pregnant; George Williams returns, much to Rex's displeasure; Lynette learns Tom's old girlfriend, has been hired at his firm again; Susan and Julie encounter strange behavior from the Young family.
George continues to worm his way into Bree's life; Lynette tries to spice up her sex life with Tom; Susan hires Mr. Shaw to investigate the Young family; Morty proposes to Sophia, making Susan relieved her mother's moving out; Felicia takes action to help Zach by planning to drive Paul from neighborhood for good.
Susan and Mike decide to move in together; Lynette takes steps to make sure Annabel doesn't come between her and Tom; Bree comes to a realization about George; Carlos' legal problems take a turn for the worse; Martha Huber's journal falls into the hands of Susan and Julie.
Bree throws Phyllis out of her house; Susan tries bravely to accept Edie's new role in Julie's life; Lynette's demanding boss, Nina, makes her miss Parker's first day of kindergarten; Gabrielle finally breaks after seeing John with an older woman; Felicia persuades Mike to watch his back for the missing Zach and Paul might come after him; Betty and Matthew try to keep their mysterious captive's presence a secret when he nearly escapes.
Susan's dear friend, Lonny Moon, gets into financial trouble and asks for her help; Lynette is forced to go out to bars night after night with her man-hungry boss, Nina; Bree is allowed to re-bury Rex amid police suspicions; Gabrielle hires David Bradley to defend Carlos in court, but Carlos rejects him; More of the Applewhite's past is shown; Fugitive Paul Young inconspicuously returns to Wisteria Lane.
Susan tries to get Paul Young arrested, while her mother pays another visit; Carlos continues serving his jail sentence, while Gabrielle tries to free him, but his lawyer refuses to represent him; Bree gets a bad rash every time she tries to be intimate with George; Lynette gets into a minor argument with Tom over her purchase of a number of very expensive business suits to impress Nina.
All the residents stress about security after the intruder at Gabrielle's; Lynette fears Tom doesn't keep his eye close enough on their offspring; Susan discovers that her biological father is nearby, and decides to meet him; Bree later gets a visit from a mysterious woman who claims that George is not who she says he is; Gabrielle has bad news for her Carlos about her miscarriage, and gets a visit from a former prison inmate of Carlos, named Hector, forcing her to face her feelings.
George stalks Bree, despite her efforts to break up with him; Lynette uses some leverage against Nina, after catching her frolicking with Stu over office politics; Carlos is finally paroled from prison and returns a new man; Susan finally meets face-to-face her birth father, and tries to begin a relationship with him.