Characters:

Mark Cohen: aspiring filmmaker, used to date Maureen, Roger's
            roommate, narrator of the story

Roger Davis: struggling musician, HIV+, Mark's roommate

Tom Collins: former professor of "computer-aged philosophy" at MIT,
             genius anarchist, HIV+, used to live with Mark and Roger

Benjamin Coffin, III (Benny): lived with Mark and Roger until
            marrying Allison Grey, now he's Mark and Roger's
            landlord.  He wants to build a cyber studio in the
            vacant lot next door.  Used to be with Mimi.

Joanne Jefferson: a lawyer, Maureen's current lover

Angel Dumott Shunard: transvestite street musician, HIV+

Mimi Marquez: lives in Mark and Roger's building, dances at the Cat
              Scratch Club, HIV+, heroine addict, used to be with
              Benny

Maureen Johnson: performance artist, Mark's ex-girlfriend, used to
                 live with Mark and Roger, currently with Joanne

Allison Grey: Benny's wife, never seen on stage, $rich$

April: Roger's former girlfriend, slit her wrists about six months
   before the action of the play begins

Plot:

The action begins on Christmas Eve.  Mark has decided to start making a new film, this one a documentary of his life and the lives of his friends.  Roger, his roommate, has just returned from six-month heroin rehab and is attempting to write his "one song glory."  Roger hasn't left the loft in a month, and says that he won't until he writes his song.

Meanwhile, Joanne is attempting to set up a stage in the vacant lot next door to Mark and Roger's building.  Benny has purchased the building and the lot and is going to evict the homeless from the latter and build a cyber studio.  Maureen has decided to protest this eviction by putting on a piece of performance art.  Joanne is having trouble, so Maureen calls Mark (her former production manager) to help.

Collins has just returned to town after seven months in Boston.  He's beaten and has his coat stolen, but Angel sees him and offers to help.

While Mark is out, Roger answers a knock on the door to find Mimi.  She asks him to "light her candle" because the power is out and she wants to shoot up.  They have a flirtatious, back-and-forth song before she leaves Roger in the dark.

On his way to the lot to help Joanne, Mark runs into Collins and Angel and brings them back to the loft to see Roger.  They all try to convince him to go out with them, but he refuses.  Mark proceeds to the lot and Collins and Angel go to the Life Support meeting, where Mark joins them later.

After the Life Support meeting, Mimi busts in on Roger demanding that he take her out.  When he refuses, she tells him that he has to live for the moment ("no day but today").  He yells at her and orders her out of his apartment.  She leaves, and after a few moments of introspection, Roger grabs his coat and walks out of the loft.

He meets up with Mark in the lot and tells him about Mimi.  Just as he's attempting to change the subject, they spot Mimi walking across the lot.  Roger apologizes to her for being rude, and they watch Maureen's show together before going to the Life Cafe with everyone else.

During the party at the Life Cafe Roger and Mimi each find out that the other is HIV+.  They sing a romantic little song and leave the Cafe together.  Joanne breaks up with Maureen.  A riot has broken out in the lot, but "oblivious, Mimi and Roger share a small, lovely kiss."

As Act II begins, it is New Year's Eve and everyone is trying to break back into the building that Benny has locked them out of.  Benny shows up and offers them the key, but not without implying that Mimi slept with him to get it.  Roger is naturally angry, but he gets over it with the help of the others.  Everyone exits, and as the lights go down Mimi buys drugs.  Maureen and Joanne get back together.

Mark was offered a job by a tabloid television show called Buzzline.  Maureen is inspired by this and decides to plan another protest, this time against the groundbreaking for Benny's project.  It's Valentine's Day, and she and Joanne are rehearsing.  They end up fighting and breaking up.

Angel is getting sicker and sicker, and on Halloween she dies.  Her funeral is so sad!  Anyway...Roger sells his guitar and buys a car because he's decided to move to Santa Fe.  Mimi is with Benny.  Maureen and Joanne are still apart, but Collins yells at everyone for being stupid (basically), and the latter couple get back together.

Mimi runs away after saying good-bye to Roger, and Benny runs off to look for her.  Mark is left alone on stage.  As he stands there, he begins to realize that by taking the job with Buzzline he is selling out.  Roger, in Santa Fe, enters and realizes that Mimi was his song all along and that he must return to New York.  Mark turns down the job at Buzzline in order to focus on his own film, inspired by Angel.

It's Christmas Eve again, and Mark is showing his film (Today 4 U) to Roger.  Roger has written his song, but no one knows where Mimi is.  The power suddenly goes out, and Collins enters with money he has gotten by hacking into an ATM.  They're singing about opening that damn restaurant in Santa Fe when suddenly Maureen screams for Mark and Roger to come help.

Maureen and Joanne have found Mimi in the park, and she's sick.  They take her up to the loft, and Roger sings his song to her.  She dies, but then suddenly jerks back to life.  Everyone is happyhappy, and the show ends with the entire cast singing together.