Adele Delfino, Susan's mother-in-law, arrives for a visit. Carlos and Gabrielle find out their tenant, Elli, has a dark secret. A full scale war erupts between Bree and Edie.

"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.