The title refers to a flood that occurs in the small town where most of the film's action takes place. It draws the two romantic leads closer, and the special effects are pretty good given the time the film was made.
This Greta Garbo silent drama, her first American (MGM) film, also stars Ricardo Cortez as the son of a domineering mother, played by Martha Mattox. The wealthy matriarch Dona Bernarda Brull (Mattox) is upset about her son Rafael's infatuation with the orange farmer's (Edward Connelly) daughter, Leonora (Garbo). So, she forbids him to see her and forecloses on the Moreno's farm. This causes Leonora great heartache, to say nothing of her family's financial condition. Using the singing talent cultivated by her wannabe father Pedro, Leonara leaves her humble home to later become a sensation on the stages of Paris, as La Brunna, where nobleman and other rich gentleman cultivate favors from her.
Meanwhile, back in their small town of Valencia where Leonora's father has passed away, Dona Bernarda Brull’s influence has brought Rafael to the brink of being elected to office. She's also arranged for her son to marry Remedios Matías (Gertrude Olmstead), the daughter of a rich hog farmer (Mack Swain). However, just before both of these events are realized, La Brunna returns to her humble beginnings to visit her mother Pepa (Lucy Beaumont) and barber friend Cupido (Lucien Littlefield). Incognito, she gives Rafael the impression that she is still poor, and nearly destitute. When the proud soon to be elected official visits Cupido, Leonara reveals that she is the famous La Brunna. Naturally, he is irresistibly drawn to her, which though it doesn't keep his inevitable election from happening, it does threaten his marriage to Remedios ... that is until his mother intervenes once again. Some time after the flood, though not on that particular night, Leonara and Rafael spend a night of passion together amidst the orange blossoms, Dona Bernarda Brull visits Pepa to tell her of the shame which has been brought upon her home.
*** SPOILERS ***
So, La Brunna returns to her life on the stage in Madrid while Rafael marries Remedios. Shortly thereafter, however, Rafael follows his Leonara to declare his love for her once again, seemingly ready to throw away his life for her. She is thrilled and, with her maid (Lillian Leighton), packs her bags to await his return. Rafael's wise lawyer friend Don Andrés (Tully Marshall) intervenes on behalf of his mother and the community he serves to convince him to do otherwise, and again Leonara is left "holding the bag". Years pass, but the two never forget their everlasting love for one another. A much older looking Rafael visits La Brunna, who doesn't appear to have aged since last they met. This time he's ready to leave his wife and two children for her, but she is unwilling to be the cause of it. He returns to Remedios, looking over his sleeping little ones while La Brunna completes another performance with adoring fans and then sits alone forlornly thinking of their love lost.