Due to a possible cholera epidemic onboard, passengers on a ship are forced to disembark at Pago Pago, a small village on a Pacific island where it incessantly rains. Among the stranded passengers are Sadie Thompson, a prostitute, and Alfred Davidson, a fanatic missionary who will try to redeem her.

The story of a poor young woman, separated by prejudice from her husband and baby, is interwoven with tales of intolerance from throughout history.

Members of a teenage gang are sent to the State Reformatory, presided over by the callous Thompson. Soon Patsy Gargan, a former gangster appointed Deputy Commissioner, arrives and takes over the administration to run the place on radical principles. Thompson needs a quick way to discredit him.

A moll, imprisoned after participating in a bank robbery, helps with a breakout plot.

After a love affair ending in an abortion, a young prison reformer submerges herself in her work. She then falls for a controversial and married judge and scandal looms again.

Reporter Sue Walker has too much inside information on the local gambling rackets to suit her sweetheart, Detective Lieutenant Jerry Brown, chief of the police Homicide Squad. When the call comes in that there has been a killing at Lefty Ross' place, a notorious gambling joint, Jerry is peeved when Sue beats him there. He discovers that gambler Jimmy Clark was killed as he answered a telephone call, and his body is riddled with bullets but Jerry can't find any weapon. Sue is amazed to see Gloria Cunningham there. Gloria's father is one of the town's leading reformers and she is engaged to District Attorney Richard Sutton. Ross decides to give Sutton all the information he needs and makes an appointment to go to Sutton's home. Once there, Ross is called to the telephone before he can give any information, and is killed in the same mysterious manner as Jimmy Clark.