Doctor Faustus is a scholar living in Wittenberg, Germany. Feeling that he has reached the ends of all traditional studies, he decides to pursue magic, and has his servant Wagner bring him Valdes and Cornelius, two men who can teach him how to perform magic incantations. Two angels (a Good Angel and an Evil Angel) appear. The Good Angel tries to convince Faustus not to pursue unholy magic, but the Evil Angel encourages him to delve into sorcery. Valdes and Cornelius give Faustus spell-books and Faustus is excited to begin casting spells and summoning spirits.
Two scholars, who know of Faustus for his reputation as a scholar, wonder what he is up to and, running into Wagner, ask him. Wagner tells them that Faustus is with Valdes and Cornelius, and the two scholars lament Faustus' interest in magic.
Faustus begins conjuring, and summons up a devil named Mephastophilis. Faustus orders Mephastophilis to do his bidding, but Mephastophilis informs him that he can do nothing that is not commanded by Lucifer. Faustus asks him questions about hell and its devils, and then tells Mephastophilis to bring an offer to Lucifer: he will give his soul to Lucifer, on the condition that he gets 24 years of unlimited power and knowledge, with Mephastophilis as his willing servant. Mephastophilis goes to Lucifer, and Faustus thinks that he has made a good deal.
Meanwhile, Wagner finds a clown and persuades him to be his servant, promising to teach him some magic in return. In his study, Faustus begins to hesitate about the deal he has proposed with Lucifer. As he debates repenting and turning back to God, the two angels appear again and try to persuade Faustus in their respective directions. Faustus renews his resolve to give his soul to Lucifer.
Mephastophilis returns and Faustus questions him about hell before officially agreeing to his deal with Lucifer. Mephastophilis demands that Faustus certify the agreement with a deed of gift written in Faustus' own blood. As Faustus attempts to sign the agreement, his blood congeals, as if refusing to sign. Mephastophilis fetches some hot coals to melt the congealed blood, and Faustus signs the agreement. Faustus immediately regrets the deal, but is distracted from his worries when Mephastophilis summons up a group of devils bringing various riches to him. Faustus then asks Mephastophilis more questions about hell. He asks Mephastophilis for a wife, but Mephastophilis cannot do anything related to marriage (a holy ceremony), so he summons a devil-woman instead.
Mephastophilis gives Faustus books containing all the knowledge of astronomy and the stars, as well as of all plants and trees. Faustus again begins to regret giving up his soul and considers repenting. At this, the angels re-appear and again make their cases to Faustus. Faustus again decides not to repent. Mephastophilis teaches him about the movement of the planets and the composition of the universe. Faustus asks who made the world, but Mephastophilis refuses to answer, as he does not want to say the name of God. This makes Faustus want to repent again and turn to God. The angels appear again, and Faustus says that he wishes to repent. At this, Lucifer appears with other devils, telling Faustus not to speak of God and Christ. Faustus apologizes and assures Lucifer that he will reject God. Lucifer entertains Faustus by summoning up personifications of the Seven Deadly Sins, which parade past Faustus for his enjoyment. Lucifer gives Faustus another book to learn from, before leaving.
A stable-hand named Robin steals one of Faustus' spell-books and tells his friend, the inn-keeper Rafe, that they should try to cast some magic spells. Wagner informs the audience that Mephastophilis has taken Faustus on a grand tour of the world in a chariot drawn by dragons, in order to learn all the secrets of astronomy. The pair is now headed for Rome.
Once in Rome, Faustus wants to see all the city's monuments, but Mephastophilis tells him to stay in the pope's private chambers and play a joke on him. Mephastophilis makes Faustus and himself invisible, and they conduct mischief as the pope and his cardinals attempt to have a banquet. A group of friars attempt to sing a dirge to drive away malevolent spirits.
Back in Germany, a vintner (wine merchant) confronts Robin and Rafe about a goblet they have stolen. The pair uses Faustus' spell-book to summon Mephastophilis in order to scare the vintner away. Mephastophilis comes, but is frustrated that he has been summoned by two lowly “slaves” (VIII, 39) for such a banal task. Meanwhile, after some more traveling, Faustus returns to Germany. His fame as a conjurer has spread far and wide. The German emperor Charles V has invited Faustus to his court, having heard about his magic skills.
At the emperor's court, Faustus indulges the emperor by calling up the spirit of Alexander the Great, essentially Charles' hero. Charles V is exceedingly impressed, but a knight of his is uncomfortable with the devilish magic and is skeptical of Faustus. Faustus repays the knight's rudeness by making horns appear on his head.
After Faustus' visit to the emperor, a horse-courser (horse-trader) finds him and asks to buy his horse. Faustus agrees but tells him not to ride the horse into water. Thinking that Faustus is trying to trick him, the horse-courser rides the horse into a pond. In the middle of the pond, the horse vanishes, plunging the horse-courser into the water. Angry, he attempts to confront Faustus, who is sleeping. He yanks on Faustus' leg to wake him up, but the leg comes right off Faustus' body. He runs off, scared, while Faustus' leg is instantly replaced by magic. Wagner informs Faustus that his company is requested at the court of a nobleman, the Duke of Vanholt.
At the Duke's court, Faustus entertains the Duke and Duchess with his magic. The Duchess asks for him to make grapes appear (it is the middle of winter and grapes are unavailable). Faustus does so, to the delight of the Duchess.
Wagner tells the audience that he is worried Faustus will die soon, as he has given his property to Wagner. In any case, Faustus continues to impress people with his magic. A group of scholars asks him to call up the spirit of Helen of Greece, the most beautiful woman in the world, which he does. An old man appears and urges Faustus to repent. Faustus is troubled and says that he wants to repent. Mephastophilis calls him a traitor and threatens to tear his flesh “in piecemeal” (XII, 59) for his disobedience. Faustus apologizes and resolves not to repent. He asks Mephastophilis to send demons after the old man, for making Faustus doubt himself. Faustus asks Mephastophilis to make Helen his lover, so that her beauty can distract him from his impending doom.
As Faustus' death draws nearer, he begins to despair and the group of scholars with him asks what is wrong. He finally tells them about the deal he has made with Lucifer and they are horrified. They go to pray for his soul. Alone on stage, Faustus realizes that he has only an hour left to live. He begs time to stand still and goes back and forth as to whether he will repent. He calls out to God, saying that one drop of Christ's blood would save him, but he is unable to commit to repenting. He tries to bargain with God, asking for salvation in return for a thousand or a hundred-thousand years in hell. The clock strikes midnight: Faustus' time is up. He cries out, making a last promise to burn his books, as devils surround him and drag him away.
The chorus delivers an epilogue to conclude the play, confirming that Faustus has fallen to hell, and telling the audience to learn from Faustus' example not to try to learn “unlawful things” (Epilogue, 6) beyond the limits of appropriate human knowledge.