Naughty Marietta is the story about a Princess who wishes to run away from marriage to a man she hardly knows and manages to sneak off to Louisiana and manages to fall in love with a local Mercenary Captain only in time to be found by her Uncle the Prince and her fiancée.

The movie begins in France, as Marie is shopping in a pet store for a pair of birds to add to her growing menagerie.  She is greeted by the people of the local area warmly and talks to them as she travels to her friend and voice teacher lives.  Once there she surprises him as he is writing a new song, one, which Marie later takes with her to Louisiana.  They sing and then join as the town bursts into the song.

Marietta then returns home to find that her Uncle has brought Don Carlos, the man the King has decided would marry her, over.  He shows her a wedding dress (black) of the house colors and then Marietta manages to persuade them to discuss the wedding plans in another room and gets an five minute ultimatum from her uncle to in which to join him and Carlos in the other room.

However while they are gone, She runs into her maid and friend Marietta Franini who has decided to join the casquette girls (basically a mail-order bride group) in going to Louisiana since she can’t marry her true love Giovanni due to being too poor.  This spurs Marie into action, taking the role of Marietta when the ship arrives and paying for the wedding of the real Marietta and Giovanni.

However, even as she is boarding the ship (and pretending a drunk man on the shore is her brother…which ends up almost not good when he decides to play along) her Uncle is searching for her and soon after she has left he boards his own ship and follows her to Louisiana.

She finally arrives in Louisiana but not everything is all right.  They are attacked by a group of pirates and are saved by a group of Mercenary soldiers paid by the government to protect citizens from Indian attacks.  Here, Marie meets Captain Richard Warrington, who happens to share her love of singing.  However the two’s first meeting is not a romantic encounter.  She considers him arrogant and he doesn’t think much better of her.  In fact after he teases her about her reaction to his singing she doesn’t talk to him for sixty miles!

Warrington and his men take the girls to New Orleans where the governor and many hopeful men await them.    He jokingly tells Marie that if she runs out of names, she can use his for one of her children.

The Governor welcomes the girls and they are taken to the local convent where later a party is held to introduce them to the hopeful men.  All are able to find a suitable husband, even Julie, Marie’s young friend from the trip over, who has decided not to marry unless she loves him has found the perfect man for her.

Marie however is trying to avoid marriage at all costs, although the men are determined to convince her otherwise.  Finally she tells them the credentials supplied were incorrect, bringing the attention of the Governor, his wife and Captain Warrington.  She pretends that she is a “women of charm” and is sent off.  Captain Warrington takes her to a room she can rent, although they get into another conversation that is half way between an argument and actual conversation.  She wishes him gone, but he still has questions he needs answered…particularly about why he thinks she is lying.

He is convinced she is lying after they have a singing competition with the help of the local marionette theater group.  Luckily for her, a group of men have come for her services and Warrington is distracted getting them to leave so she makes her exit from the area, much to Warrington’s surprise.

However, after a meeting with the Governor about her (almost getting the Governor in trouble with his wife!) he finds her acting in the Marionette Theater and confronts her in her dressing room only to be told that he wasn’t welcome there.  Her new boss warns Marie that Warrington is known as a heartbreaker and she should avoid him, which she agrees.

However, outside she is once again confronted by Warrington who convinces her to join him in a tour of the town.  They end up getting into a discussion about love, which Marie has yet to really believe in.  They end up near a local cuisine dinning area where Warrington’s friends and men under his command are eating already.  Marie convinces him to eat there, although they are distracted by the bad eating habits of Abraham and Ezekiel and later by their interesting medical advice (brought on by her flowers).

Later on a boat trip, Warrington admits he’s in love with her in song, but she is unsure on how to respond.  She believes she may love the Captain as well but isn’t ready to admit it.

However, when they get ashore, they are greeted by another soldier (this one from the colonial troops) who has realized that Marie is a Princess and not the charming Marietta.  Warrington is confused and almost gets into a fight with the other man when he asks that Marie accompany him to the Governor’s palace.  Marie goes.

She converses with the Governor who is afraid that the Prince will find out how Marie was treated.  The Governor’s wife prepares a room for the Princess and shows her to the room, but not before reminding her husband that his conversation with Warrington was not as nicely disguised, as he would hope.

Marie is attended by some ladies of the court and is prepared for a ball.  Julie shows up to talk to her friend about Warrington when the Prince shows up to tell her that Carlos has come and they would leave that evening for France.

Marie is upset, as she will not get to see Warrington again, but is even more afraid if he does come when the Prince tells her that Warrington will be killed for Treason if he comes to see her.

But Warrington does come to see her and manages to get alone long enough to get out of her that she has a song to sing him too and that she is leaving in two days.  The Prince finds them together but Marie assures him that Warrington was only there because she wanted to thank him and the Prince is convinced.  The Governor tries unsuccessfully for the second time to convince Warrington to leave town before he is killed.  He almost achieves that but Marie, after several people beg her to sing and she realizes she can sing the song, starts to sing the song she brought from her voice teacher’s in France.

The song transfixes everyone, including Warrington who begins to sing duet with her as she finishes the song.  Everyone notices that they are singing to each other, including the Prince so after she makes it to her rooms, he comes over and tells her that she is to get ready immediately for they were leaving. 

Warrington, who has realized she would not have sung that song if it was not the last time they would see each other, sneaks into her room and convinces her to run away with him.  They lock the door on the Prince, and manage to get downstairs before the Prince catches them and orders the two guards to take them to the Governor’s office.

However, Abraham and Ezekiel have replaced the normal guards and they help them escape into the wilderness to their happy ever after.