Rock Opera Plot

The Rock Opera tends to follow a fairly standard plot, in three acts. They tend to be cynical stories about failed rebellion.

In Act 1, the protagonist is introduced. There is often some sort of formative experience that somehow sets them apart from other people.

The eponymous character of Tommy by The Who witnesses a murder and becomes psychosomatically deaf, dumb and blind.
The nameless protagonist of 2112 by Rush discovers a guitar.
Mega Man from The Protomen's titular rock opera is built as a robot, after his (also robotic) brother was presumed KIA. After much brooding on the risks of rebelling against the Orwellian society created by Dr. Wily, decides to follow in his brother's footsteps.
- In the prequel second album, the Rock Opera Plot begins in the second half. In the first half, Dr. Light had his work stolen and his girlfriend murdered by Wily, who then set up a propaganda apparatus throughout The City to frame Light, driving him out of town so he could consolidate his own power. Jumping 20 years into the future, a young free-thinker named Joe refuses to accept the superficially pleasant, Orwellian dictatorship that The City has become under Wily's leadership.
Elphaba from Wicked is born with bright green skin.
Pink, from The Wall is born into a broken home, his father having been killed in the war and his mother having become obsessively protective.
Snow from the Spock's Beard album of the same name is a teenage albino who kept to him self as he grew up. He then realizes that in touching people he can see their past, present, and future and use that information as a form of ultimate Freudian analysis to heal them. He sets off to New York City to help people.
The protagonist of Green Day's American Idiot is introduced in his namesake track, "Jesus of Suburbia". He is dissatisfied with life in his city, being a powerless desensitized "everyman".
Nikki, the protagonist of Queensrÿche's Operation Mindcrime, a drug addict who is dissatisfied with the current state of political affairs, joins a terrorist group.
Jonathan, the protagonist of W.A.S.P.'s The Crimson idol, was hated by his parents, a hatred that intensified when his "perfect" brother died. He runs away from home to become a rock musician. He hopes that one day his success will make his parents come to see him as a good person.
Imp/Buddy, hero of the Music With Rocks In novel Soul Music, flees Llamedos after a blazing row with his father (who doesn't appreciate music and wants him to be a druid) and swears to become the greatest musician who ever lived.
Ziggy Stardust is overwhelmed by the impending end of the world and disillusioned from the hippie days by the destructive nature of love.
The Worm, protagonist of Marilyn Manson's Antichrist Superstar is a broken, abused individual, a member of the servant caste in a world ruled over by an Ubermenschian elite known as "The Beautiful Elite".
Andrew Jackson in Bloody Bloody Andrew Jackson is the only survivor of his entire family. He leaves his homeland and sets out for the frontier.
In The Hazards Of Love, Margaret meets William, a shapeshifting young man who lives in a huge forest of uncertain magical content. They fall in love and she falls pregnant, so she leaves her home and they plot to run away altogether.
David Koresh Superstar—a slightly dubious case—tells the story of a young man named Vernon Wayne Howell, of Houston, who after finding himself to be an outcast in the various communities and churches he tries to join, throws in his lot with the Branch Davidians in Waco.

In Act 2, the protagonist discovers some innate ability and that the powers that be in their world are corrupt and evil. They use their ability to confront authority and for a while, it looks like they're going to win.

Tommy turns out to have amazing pinball skills. Meanwhile, he is diddled literally by his uncle and figuratively by his agent. He's tortured by his cousin and his parents do lots of stupid things that don't help him at all (like leaving him with his uncle, cousin, and the Acid Queen). He slowly acquires a cult of personality.
The protagonist of 2112 learns how to play the guitar and write his own music and brings this knowledge to the ruling Priests of Syrinx, in the hope that they can use it to enrich society.
After fighting off Wily's robotic hordes, Mega Man discovers his brother did not in fact die, but defected to Wily's side after deciding humanity was not worth saving.
- In the second album, Joe attempts to leave The City. After an attempt is made on his life by Wily's robotic assassin, he teams up with Dr. Light with the intent of destroying Wily's broadcast tower in the hopes that stopping the constant propaganda will shock the citizenry out of their stupor and give Light a chance to kill Wily.
Elphaba turns out to have magic! The Wizard promptly tries to exploit her desire for recognition to use said magic to betray her friends, after which Elphaba rebels and uses her magic to ruin The Wizard's plans and make a daring escape.
Pink becomes a rock star, but shuts himself away emotionally in the process. While high on drugs (possibly heroin), Pink revisits the events of his life and decides it might be best to open up.
Snow gets to New York City and proceads to help many of the city's less fortunate such as the homeless, junkies, prostitutes, and gang members. He sets up a ministry in Central Park and devotes himself fully to the crowds of people who come for his advice.
Jesus creates an alternate, rebel personality, St. Jimmy and falls in love with the revolutionary Whatsername.
Nikki becomes power-drunk as a hitman for the terrorists, but his conscience (and his love for hooker-turned-nun Mary) moves him to renounce his cause.
Jonathan is corrupted by life as a rock star, falling in with Corrupt Corporate Executives, drug addicts, and other scum and is haunted by a prophecy from a Gypsy tarot reader who predicted that he would fall from his newfound fame if he kept his reckless lifestyle up. Eventually he becomes addicted to prescription drugs and uses corrupt doctors to obtain them. His parents still despise him, but he has a fanbase of millions and goes on blockbuster world tours full of wild partying and debauchery.
Buddy arrives in Ankh-Morpork, where he discovers a mysterious guitar and invents Music With Rocks In. This attracts the attention of CMOT Dibbler, who wants to make money off him, and the Guild of Musicians, who want to see him destroyed. Buddy remains steadfast in his vision of a Free Festival, and enthusiasm for the new music sweeps across the Disc. However, the guitar and its music is killing him, and he's becoming less human.
Ziggy is Touched by Vorlons and learns he can save the world with The Power of Rock.
The Worm begins a revolution, fashioning himself into the demagogic Little Horn. The oppressed people of the world flock to him as a saviour, and he overthrows The Beautiful Elite, installing himself as a benevolent dictator.
Andrew Jackson becomes a famous military leader and able politician, representing the interests of the everyman against the elite. He founds the Democratic Party and becomes President of the United States.
William's adoptive mother, the Forest Queen, forbids him from leaving her sight again; he makes a deal with her to only spend one more night away from her, planning to escape with Margaret that night. Meanwhile, unbeknownst to the main characters, the Rake arrives on the scene.
After the death of the Branch Davidians' leader, Lois Roden, Vernon acquires control of the sect, renaming himself David Koresh and taking advantage of the position—drawing, inadvertently, the interest of the ATF.

In Act 3, whatever revolution the protagonists were hoping to foment fails miserably and they are slowly but surely ground into the dirt.

In Tommy, his mother smashes the mirror he saw the murder in, causes his senses to return. Believing that his experiences have led him to enlightenment, he calls his followers to dull their own senses and play lots of pinball. His followers eventually come to the conclusion that the eponymous character is nuts, and leave him.
The protagonist of 2112 has his guitar smashed and dreams of a past golden age where creativity was nurtured by society. Unable to bear the thought of living in a world so unlike his dream, he kills himself - just before the ships from the Golden Age, who had simply left Earth, not died out, return to free it from the Temples. Too late for the protagonist, though...
After facing his brother in a Mexican Standoff, Mega Man gives in to the urgings of an assembled crowd demanding he kill him. Only after he does this does he understand his late brother's reasons for defecting, and leaves the people he set out to save to be slaughtered by Wily's robots.
- The end of the album has Joe succeeding in planting the bomb. It explodes too soon for him to get away, however. As Dr. Light sees his burning body fall from the top of the tower, he quickly discovers that not only did Wily have backup transmitters set up, but this act of terrorism gave him the excuse he needed to reveal an army of assassin robots and declare martial law, setting up the utter Dystopia of the first album.
While Elphaba has magic, The Wizard has power, influence and propaganda. He manages to turn the Munchkin people and even former close friends into a lynch mob who hunt her down.
Pink's agent snaps him out of the trip and forces him to perform. The concert quickly degenerates into a hate rally before Pink's own conscience puts him on trial and finds him guilty, demanding he tear down the emotional wall he has created. The Wall itself provides no definite conclusion, but its follow-up The Final Cut suggests that Pink contemplated suicide before reconnecting with his ex-wife.
Snow, engaging in a completely selfless existence, falls in love with someone who comes to see him in Central Park. She rejects him, calling him a freak and he spirals into despair, abandoning his ministry. Living in squalor he meets one of the junkies he saved who has since returned to drugs. The junkie takes Snow to a club where he OD's and wakes up in a hospital room surrounded by people he had helped. God tells him that he doesn't have to make it his job to save everyone.
St. Jimmy kills himself, Jesus decides to go back home, and never sees Whatsername again, eventually forgetting her.
In retaliation for his trying to walk away, Nikki's former terrorist pals frame him for murder; he winds up in a mental institution, reliving the events depicted in the album ad infinitum.
- In the sequel story, Operation: Mindcrime II, Nikki is released from jail 18 years after the events of the first album. He goes out for revenge and kills Dr. X, but does not get any satisfaction from it. Realizing the only times in his life he was truly happy were with Mary, he commits suicide and the two are reunited in the afterlife.
Jonathan burns out on drugs and begins to succumb to despair. He calls his parents one night, begging to reconcile. They answer "I Have No Son". Jonathan crosses the Despair Event Horizon and hangs himself with his guitar strings at that night's concert.
Buddy makes a desperate escape from the Musicians' Guild, which results in his being killed in a cart crash. Death and Susan manage to arrange things so he doesn't die, but only by removing Music With Rocks In from history entirely. Imp is now a fried fish salesman in Quirm. (This being Discworld it's not an actual Downer Ending, but it's still on the bittersweet side.)
Ziggy alienates his band, falls into a mire of sex and drugs, and, despondent, ultimately lets himself be killed by overzealous fans. It's not even clear whether the world was actually saved.
Little Horn realizes his sycophantic disciples have merely transferred their adoration from The Beautiful Elite to him, instead: they don't want to be saved, they just want a new dominator. Crossing the Despair Event Horizon, he sheds the Little Horn persona to become The Antichrist Superstar - an Omnicidal Maniac worse by far than his former oppressors. After spearheading a scorched earth campaign and ushering in the apocalypse, he stands alone amidst the desolation, concluding that "when all of your wishes are granted, many of your dreams will be destroyed".
Populism blows up in Jackson's face when the American people begin to resent bearing the guilt of bad policy decisions. Jackson disobeys the Supreme Court in order to relocate the Native Americans from their homes, polarizing the country, and Jackson alienates many of his former allies with his stubbornness and short tempter. Eventually he pronounces the country ungovernable and wallows in self pity.
The Rake kidnaps Margaret and, with the Forest Queen's help, absconds across an impassable river. William follows and begs the river to let him cross, saying it may take his life when he returns. He arrives in time to save Margaret (probably) and see the Rake dragged off by the ghosts of his children or something along those lines. And then William and Margaret drown together, having married with the river as their witness.
A planned ATF raid goes horribly wrong, setting off a 50-day siege that ends in fire, blood, and death for most of those involved. Surveying the wreckage, Lois' ghost, or possibly just her vocalist, muses over what went wrong, while in the future, Timothy McVeigh wrecks more of the aforementioned fire, blood, and death on innocent bystanders in the Branch Davidians' name.

An exception to this plot formula is The Lamb Lies Down on Broadway, because no-one really has a CLUE what that's about.