Ian proposes to Susan. The Scavo pizzeria prepares for its grand opening. Mike visits a hypnotherapist in hopes of remembering Monique. Gabrielle's romantically interested in a lawyer, but he's working for Zach who wants her for himself. Bree is hospitalized after a fall, after being tricked to climb on a ladder to retrieve Monique's teeth.

Edie gets an unexpected visit from her son. An unexpected pregnancy causes complications. Victor Lang, a man in his 40s running for mayor of Fairview, introduces himself for Gabrielle. The deceased Rex Van De Kamp narrates.

"The Gun Song" is the 86th episode of the ABC television series, Desperate Housewives. It is the sixteenth episode of the show's fourth season, and the first half of the two-hour season finale. It aired on May 18, 2008 in the United States.

In the aftermath of the plane crash, the residents of Wisteria Lane think about what their lives might have been like had they made different choices. Susan contemplates a life with Karl had she not left him. Bree considers life without Orson. Lynette thinks about a future with her unborn twins. Carlos reflects on how Gaby would be as an over-protective mom and Angie ponders the consequences should her secrets be revealed.

Paul finds out that Beth is Felicia Tilman's daughter while a therapist asks Carlos and Gabrielle to erase Grace from their lives. Susan finds out she needs to go to the hospital every 48 hours and Renee finally tells the secret between her and Tom to Lynette. Orson returns and Bree gets torn apart with her feelings between Orson and Keith and detectives try to find the person responsible for shooting Paul Young.

Susan's mother and aunt visit her at the hospital, Lynette plots revenge against Tom, Gabrielle becomes increasingly obsessed with getting Grace back and Bree wants to be friends with Beth.