The narrator introduces himself right off the bat as an invisible man. Hi, invisible man.
He lives off the grid, in a warm hole in the ground where he is hibernating in anticipation of future direct, visible action. But before all this direct, visible action happens, he needs to detail his road to recognizing his invisibility. We get context when we learn that the narrator's grandparents were former slaves freed after the Civil War.
On his deathbed, the narrator's grandfather, who had been considered a meek man, confesses anger towards the white-controlled system and advocates using the system against them. The narrator dismisses his grandfather's words and goes on to live a meek and obedient life as a model black student. After writing a successful speech on the importance of humility to black progress (i.e., the idea that blacks can progress as long as they recognize whites as superior), he is invited to give the speech to leaders of his town. The narrator is super-excited to give this speech.
Fast forward to speech day: the narrator is forced to strip off his clothes and fight a blindfolded "battle royal" with other young black men in front of white town leaders. Definitely not a speech. Only after the young men fight, egged on by drunken town leaders, is the narrator allowed to give his speech. His big moment has arrived, but the town leaders barely listen. They reward him well, however. At the close of his speech, the narrator is presented with a fine briefcase and a scholarship to a black college.
The narrator recalls that the college grounds were beautiful (remember this whole story is being told by a guy currently living in a manhole). He remains a model student and aspires one day to work with Dr. Bledsoe, who heads the school. When he is selected to drive Mr. Norton, one of the school's founders and a rich white millionaire, around the grounds, the narrator is excited. And then things go horribly wrong.
The two visit old slave quarters and hear the story of a man named Trueblood, who apparently impregnated his daughter. In need of some fortifying liquids, Mr. Norton orders the narrator to take him to the nearest bar. This happens to be an insane-asylum-and-bar hybrid. (What?!) Well, so much for the narrator someday working with Dr. Bledsoe—the guy kicks him out of school and tells him to go look for work in Harlem, New York. He hands the narrator some letters of recommendation and wishes him luck.
The narrator is excited about his prospects in Harlem, but Dr. Bledsoe's letters of recommendation aren't doing any magical employment tricks. Turns out the letters of recommendation are actually the opposite—letters asking the recipient to not help the narrator. Ouch. Crushed and dismayed, the narrator ends up taking a job at Liberty Paints. While there, he makes white paint, is mistaken for a fink (a hired strike-breaker), then mistaken for a unionist, and then is accidentally blown up and used as a lab rat in the company hospital. All-around great first day on the job. It's also the narrator's last day. We don't blame him.
A friendly, motherly woman named Mary Rambo takes the narrator into her house and, for lack of a less clichéd phrase, believes in him. This belief is borne out when the narrator witnesses an old black couple getting evicted on the streets and feels compelled to give an awesome impromptu speech (to a listening audience, no less).
One of those listening is a white man named Brother Jack, who initiates the narrator into the Brotherhood, a multiracial organization with communist undercurrents. The narrator moves out of Mary's house, makes some good money, and learns the ways of the Brotherhood. He makes some excellent speeches (to people that listen), and gains increasing prestige within the Harlem community.
Big mistake, apparently. The Brotherhood re-assigns the narrator to attend to women's issues downtown, which is equivalent to your swimsuit company transferring you to Juneau, Alaska.
After a couple weeks, the narrator returns to Harlem to learn that Tod Clifton, a fellow young black Brother, has been missing for a number of weeks. Harlem itself has undergone a lot of change—much of the work the narrator put into the community has disappeared. The narrator is further thrown for a loop when he finds Clifton selling Sambo dolls on the street. He witnesses a police officer shoot Clifton. With Clifton dead, the narrator urgently tries to contact senior members of the Brotherhood to organize a funeral service, but ends up taking matters into his own hands and organizes a public funeral. Mistake!
The Brotherhood summons the narrator to a meeting during which they chastise him for taking matters into his own hands. They call Clifton a traitor for selling the racist Sambo dolls, and they reprimand the narrator for organizing a public funeral. Apparently, public demonstrations are no longer part of the Brotherhood agenda. Brother Jack instructs the narrator to visit Brother Hambro, who will outline the new program.
The narrator decides to visit Brother Hambro that night, but on the way, he bumps into Ras the Exhorter, a black nationalist who conveniently uses the situation to stir up anti-Brotherhood sentiment. It's a bit of a dangerous situation for the narrator, who sees two men ready to follow him into a who-knows-what kind of dark alley. Deciding that a disguise would be the best course of action, the narrator purchases a prop or two and promptly starts being mistaken for a man called Rinehart. This Rinehart character is a reverend, a gambler, a fighter, and a pimp, among other identities.
The narrator realizes that he can have multiple identities—that's the benefit of being invisible. Deciding to discuss the idea with Hambro, the narrator meets up with Hambro and learns that the Brotherhood is planning to sacrifice the people of Harlem in service of a greater, unnamed cause. The narrator decides to spy on the Brotherhood and figure out their true intentions, but is unsuccessful.
Harlem erupts into a race riot, and the narrator speculates that this was the Brotherhood's plan all along. Extremely upset, he continues running down the streets of Harlem as Ras the Exhorter (now Ras the Destroyer) urges further destruction. Ras calls for the narrator to be apprehended, but the narrator eludes capture after a brief confrontation.
He tries to go to Mary's house, but ends up falling down a manhole. When he awakens, he realizes the full extent of the Brotherhood manipulation and gets angry. He realizes he needs a plan of action and decides to hibernate until then. He tells us that writing his story was helpful, and that he's ready to come out of hibernation. He wonders if his story is speaking for us as well as himself.