Small-town scandals erupt when a repressed woman deals with her daughter's move into adulthood.

As stranger Michael Rossi drives into the small New England town of Peyton Place in search of employment, he passes a broken-down shack owned by Lucas Cross, a bitter, self-pitying drunk. Lucas' world-weary wife Nellie works as a housekeeper for Constance MacKenzie, the young widow who owns the local dress shop. After a contentious interview, the highly idealistic Michael is hired by Leslie Harrington, the owner of the mill and president of the school board, as the new high school principal. At the end of the school day, Connie's studious daughter Allison, an aspiring writer, meets her best friend, Selena Cross, Nellie's daughter, at Connie's dress shop. When the aloof, proper Connie objects to Allison inviting teenage sexpot Betty Anderson to her upcoming birthday party, Allison bristles. Later, at the party, Betty arrives with Rodney Harrington, her childhood sweetheart and heir to the Harrington fortune. Also attending the party is Selena, her fiancé, Ted Carter, who dreams of becoming a lawyer one day, and Norman Page, a sensitive youth who is dominated by his overbearing, possessive mother. After the roguish Rodney insists on turning out all the lights, Connie returns home and angrily ends the party, thus humiliating Allison. That Sunday after church, Michael visits the MacKenzie house to announce that Allison has been named valedictorian of the senior class. While there, Michael invites Connie, who had previously rebuffed him, to chaperone Allison's graduation dance. Soon after, Harrington calls Rodney into his office and offers him a new car if he will break his date with Betty, whom he calls the "local tramp," and take Allison to the dance instead. At the dance, Betty, peeved at Rodney for breaking their date, flirts with him and then slugs him with her purse. After the dance ends, Michael, alone with Connie, kisses her, but she again rejects him. Ted escorts Selena home, and after he leaves, the lecherous, drunken Lucas rapes her. Following graduation, Selena discovers that she is pregnant and turns to Dr. Mathew Swain, the kindly town physician, for an abortion. After Selena confides that Lucas raped her, the outraged Swain threatens him with jail, then forces him to sign a confession and orders him to leave town. When Selena returns home later that night, Lucas drunkenly chases her through the woods in revenge. After losing Lucas, Selena trips and falls down a hill, causing her to miscarry. To protect Selena's reputation, Doc Swain performs an appendectomy on her. At the Labor Day picnic, Betty and Rodney go swimming in the nude, and then Betty dares Rodney to defy his father and marry her. Norman and Allison also go for a swim in the lake, and when the town busybody spots two young people swimming naked, she assumes that they are Norman and Allison and spreads rumors about them. Michael, meanwhile, has invited Connie for a drive in the country, but when Michael tries to kiss her at evening's end, Connie lashes out that men are only interested in sex. Later Connie hears the rumors about Allison, and refuses to believe her daughter's denials. In a moment of anger, Connie coldly reveals that Allison was illegitimate. Stunned, Allison runs upstairs and discovers that Nellie, unable to deal with Selena's rape, has hanged herself. Soon after, Rodney informs his father that he and Betty are married. Harrington wants the marriage annulled, but Rodney assures his father that he has always loved Betty and has decided to quit college in order to take a job in the mill and support his wife. No longer able to tolerate life in Peyton Place, Allison boards a bus bound for New York. With the bombing of Pearl Harbor, the boys of Peyton Place go off to war, and Rodney asks his father to take care of Betty. Later, when word comes that Rodney was killed in combat, Harrington reconciles with Betty and welcomes her to the family. At Christmastime, Connie visits Michael to apologize for her abrasive behavior. After she confesses that she was a married man's mistress, Michael embraces her and promises to care for her always. On Christmas Eve, Selena is shocked when Lucas appears in a Navy uniform and assaults her. In a fit of rage, Selena clubs him to death and buries his body in the back yard. At Easter, several naval M.P.'s come looking for the AWOL Lucas. After they leave, Selena breaks down and confesses to Connie, who then notifies the state police. When Selena is charged with murder, Allison returns to Peyton Place to offer her best friend support. On the train home, Allison meets a newly confident Norman, now a sergeant in the military. Fearful of disgracing Ted, Selena begs Doc Swain not to divulge the rape and he reluctantly accedes to her wishes. When the prosecutor accuses Selena of premeditated murder, however, Swain presents Lucas' confession as evidence of self-defense. After Selena is acquitted, Allison, who has shunned her mother throughout the trial, runs after Connie and Michael. At the doorstep of the MacKenzie house, mother and daughter embrace and Michael ushers Connie, Allison and Norman home.