A family that is breaking up are among the passengers on the fateful voyage, and each of the four undergoes psychological changes before they discover that the women will live and the men will die.
The Titanic in the fog is ready for its maiden voyage. Captain Edward John Smith (Brian Aherne) says there will be 2,200 aboard, and he receives an old flag as a gift. Sandy Comstock (James Todd) sees Julia Sturges (Barbara Stanwyck), who says her husband is not coming. Richard Ward Sturges (Clifton Webb) asks for passage on the Titanic and insists on going. He buys a ticket from Mr. and Mrs. Uzcadum (Marta Mitrovich) by persuading them they can buy more land. Passengers board the ship.
Captain Smith orders her taken to sea. Richard comes up to first class, though Earl Meeker (Allyn Joslyn) says not to do that. In the dining room Richard joins Julia and argues with her alone. Julia is tired of traveling and is taking Annette Sturges (Audrey Dalton) and Norman Sturges (Harper Carter) back to Mackinac, Michigan.
Drunk George Headley (Richard Basehart) tries to dictate a telegram that he is coming home. Maude Young (Thelma Ritter) says he is running away. Giff Rogers (Robert Wagner) sees Julia and starts talking with her. She says her daughter’s name is Annette, and he asks her to put in a good word for him. Richard tells Julia he bought some clothes. Richard talks to Annette about an invitation she missed with an eligible young man. Julia says they are going home for good. Annette asks her father if he will stay at home, and she says she will return to Paris with him. Norman tells his father he wants long trousers. Julia tells Richard that she wants Norman to stay in America and says she will fight for him. He says he would never give up his son; but she says he is not his son.
Giff hopes to dance with Annette, and she agrees. Richard has Mrs. Uzcadum sign papers. Julia tells Richard about the father of Norman, and he says that Norman belongs to her now. Richard finds a note from Norman about playing shuffleboard, and he joins a bridge game. On the deck George tells Julia about the stars and admits he is drunk. She takes him to his cabin, and she finds a Bible and realizes he is a minister. He says he is no longer a priest because he is an alcoholic.
The ship is near the iceberg field. Passengers sing “Holy, Holy, Holy” in a church service, and Captain Smith prays. Despite the iceberg field he says they need not reduce their speed. While playing bridge, Richard tells Norman to get a new partner for shuffleboard. Maude says a word can do more than a hickory stick. On the deck Annette apologizes to Giff for walking off, and he shows her how to do the Navajo Rag. Giff is so happy he throws his hat into the icy sea. Julia asks Richard to have dinner with the children, and he asks her to give them the explanation. Richard admits he has no character. George sends a telegram to his family in Boston. Captain Smith checks on the position of an iceberg but does not alter course because the weather is clear. An officer thinks they could reach another iceberg before day. Giff kisses Annette.
At 11:36 they see an iceberg ahead. They alter course but scrape it while passing, cutting a large hole that lets in water. Captain Smith gets damage reports and realizes they cannot be repaired. He orders passengers to put on life-jackets and the boats to be lowered. He tells Richard the ship is going down, and Richard realizes there are not enough lifeboats for the men. They send up a flare, hoping another ship can come to them. Richard tells his family to dress warmly. Richard goes below and helps the Uzcadum family. Giff tells Annette he is glad he met her. Julia tells Richard she is sorry about everything, and he revives their courtship. They kiss goodbye. Richard says goodbye to Annette and Norman. Women and children get in the lifeboats, and the men are needed aft. Norman gives up his place to a woman who came late. Julia learns he is gone and cries. Giff climbs down the ropes to untangle them so that a boat can be lowered. He falls in the sea and is taken into a boat. Captain Smith learns where a ship will be able to pick up those in the lifeboats by dawn. One end of the ship is sinking. Maude discovers Mr. Meeker in the boat dressed as a woman. Captain Smith learns the water has almost reached the boilers. He asks the orchestra to play. An old woman declines to leave her husband. Water causes the boiler room to blow. George goes in to try to help. Norman finds his father, who admits he loves him. The telegraph line goes down, and Captain Smith makes his last log entry. The men sing, “Nearer My God to Thee.” An explosion is heard, and the ship goes under. In 19 lifeboats 712 people survived.
This drama is made poignant by the historical context that forces the characters to face the end of some of their lives. The sophisticated but superficial Richard is brought to realize his deeper feelings by the approach of his death. The true story of the men letting the women and children survive says much about the gentleness of the men in the society.