So, get me up to speed on Desperate Housewives

If it helps, Eve, I’ll try to give you a synopsis of the current main characters in terms of their basic caricature, rather than their involvement in plot twists. It might be easier to follow and more meaningful as you jump into the thing after two seasons:
Mary Alice Young

Dead narrator. Tells the story as it unfolds, and wraps things up neatly at the end of each episode, usually under a single theme.

Bree Van de Kamp

Melancholy temperament. Obsessive compulsive perfectionist. Each utensil must be exactly one inch from table edge. Cup handles must be at 30 degree angles from diners. Blouse must be wrinkle free. There is a right way and a wrong way to say and do everything.

Rex Van de Kamp

Dead husband. Now the subject and object of much drama for Bree.

Andrew Van de Kamp

Son of Bree. Hates her. Gay.

Danielle Van de Kamp

Andrew’s sister.

Susan Mayer

Magnet for tragedy. Heart of gold, but everything she touches turns to shit. Do-gooder who ruins lives. Skips merrily along the Road of Good Intentions, dragging everyone to hell along the way. Hapless. Accident prone. Emotional. Kind hearted.

Karl Mayer

Susan’s ex.

Julie Mayer

Susan’s daughter. Object of affection for psychotic Zach. (See Zach Young).

Lynette Scavo

Just trying to get by, but encounters obstacles at every turn. Three or four bratty kids she can’t control. Unfulfilling job she calls a career. Willing to do drugs to tune it all out. Resigned to her fate. Has a sense she that doesn’t belong here, and missed the boat of fortune somewhere along the way.

Tom Scavo

Lynette’s husband. Dumb but endearing jock. House-husband who used to be primary bread winner. Seen by Lynette as a source of worry, paricularly in how he takes care of the kids.

Gabrielle Solis

Eye candy for men. Cute. Spunky. Sexy. Materialistic. Single minded. Hates the new nun, Mary. All she wants is the best life has to offer. Untrustworthy. Despite all this, still somehow likeable.

Carlos Solis

Gabrielle’s husband. Oblivious.

Mike Delfino

Plumber and private dick. Gruff. Blunt. Yet quiet. Used to be Susan’s boyfriend. Now he hates her. Moved to the neighborhood to investigate the death of his boss’s daughter, Zach’s mother, and a woman apparently murdered by Mary Alice Young and Paul. (See Paul Young). Turned out to be Zach’s father.

Paul Young

Mary Alice’s husband. Private and secretive. Probably has the most dramatic secrets. Now knows that Zach is Paul’s son.

Zach Young

Psycho kid with severe attention deficit. Freaked out by his own weird life history. Just returned home. Has the hots for Susan’s daughter.

Edie Britt

Susan’s nemesis. Whore.

Betty Applewhite

Newcomer. Kept mildly retarded son (apparently, husband possibly, despite script elements) locked in basement. Good hearted. Sweet. Tries to stay out of everybody’s business.

Matthew Applewhite

Betty’s son. Assisted in keeping his brother (or father) in basement. Next season should develop these characters more fully.

George Williams

Psycho stalker who murdered Bree’s husband and tried to kill her psychiatrist. Now dead, but still a part of plot.

John

The lawn boy. Eye candy for women. Was Gabrielle’s play thing, but took it all too seriously. Once he became a threat to her income source, she dropped him.