->''Once upon a time - in 1941 to be exact - there live in a great, tall forest - called New York - eight men who were writing an encyclopedia. They were so wise they knew everything: the depth of the oceans, and what makes a glowworm glow, and what tune Nero fiddled while Rome was burning. But there was one thing about which they knew very little - as you shall see...''
-->-- '''Title card'''

A 1941 ScrewballComedy about eight professors who are trying to compile the world's largest encyclopedia. Realizing his books on slang are out of date, English Professor Bertram Potts (Creator/GaryCooper) leaves the communal library/house where they work to find research material. There he meets burlesque dancer Sugarpuss O'Shea (Creator/BarbaraStanwyck), who needs a place to hide from the cops so she can't testify against her boyfriend: mobster Joe Lilac (Dana Andrews). She stays with Potts and uses his affection for her to her advantage. Naturally, she falls InLoveWithTheMark and HilarityEnsues.

From a script by prolific Hollywood writer Creator/BillyWilder and directed by Creator/HowardHawks with a score by Music/AlfredNewman. Nominated for three UsefulNotes/{{Academy Award}}s, including best actress and best story.

Remade as the 1948 {{Musical}} film ''Film/ASongIsBorn''.
!!Tropes found in Ball of Fire include:
* {{Adorkable}}: Bertram UpToEleven.
* BadassBookworm: the professors and Bertram, when it comes time [[TookALevelInBadass to take a step up]].
* {{Burlesque}}: If they ever remake this film Sugarpuss will probably be a stripper.
* CampStraight: Professor Oddly is a rather mannered and slightly effeminate old gentleman (presumably due to having come of age in a more formal era), but he's the only one of the professors to have any previous romantic experience with women.
* DepartmentOfRedundancyDepartment: Sugarpuss's habit of saying "on account of because", much to Bertram's annoyance. She reads his books and correctly diagnoses this as a [[http://en.wikipedia.org/wiki/Pleonasm pleonasm]].
* {{Expy}}: The other seven professors for [[Disney/SnowWhiteAndTheSevenDwarfs the seven dwarfs]].
* GrammarNazi: Bertram, being the grammarian in the encyclopedia group. He particularly likes to harp on the split infinitive rule, that favorite of pedants. Later in the film, his passion for Sugarpuss loosens his grip on grammar.
* InLoveWithTheGangstersGirl: Bertram. Since this is a comedy, he gets the girl instead of getting a bullet between the eyes.
* InLoveWithTheMark: Sugarpuss, much to her own surprise.
* LeaveTheTwoLovebirdsAlone: The other professors drag Professor Oddly out of the room when he tries to tell Sugarpuss and Bertram to take it slow.
* MsFanservice: Sugarpuss, played by Barbara Stanwyck, wearing dance clothes in her first appearance.
* OneHeadTaller: Even in heels, Sugarpuss needs to stand on a couple of reference books to kiss Bertram.
* ObliviousToLove: Bertram at first.
* SeriousBusiness: Making damn sure that encyclopedia is as accurate and up-to-date as possible. This was, mind you, before Wikipedia.
* SesquipedalianLoquaciousness: All of the professors. Parodied when Bertram, who needs to stall for time to get the drop on a couple of {{Mooks}}, launches into a long lecture that consists of a lot of gibberish, but with very fancy words.
* SettleItWithoutWeapons: Sort of. After the good guys have already captured the bad guys and the cops are on the way, a thoroughly pissed-off Bertram gives his gun to one of the other professors and challenges Joe Lilac to a fistfight.
* [[ShoutOut/ToShakespeare Shout-Out: To Shakespeare]]: Bertram quotes ''Theatre/RichardIII'' when giving Sugarpuss the engagement ring.
* SixIsNine: A poorly secured 9 on the front door of a motel cabin falls over and becomes a 6. This causes Bertram to enter the wrong cabin and accidentally pour his heart out to Sugar.
* SpeakNowOrForeverHoldYourPeace: While these exact words aren't said, Bertram and his friends do have to break up Lilac's wedding in the climax.
* TickleTorture: The professors uses this (with a feather) on Pastrami, one of Joe Lilac's {{Mooks}}, to get him to say where Lilac is going to (try to) marry Sugarpuss. It works.
* TitleDrop: A newspaper headline refers to Sugarpuss as the "ball of fire" the professors unknowingly smuggled past the cops.
* TookALevelInBadass: All of the professors near the end, and Bertram in particular.
* UptightLovesWild: Sugarpuss the burlesque performer throws a wrench into the life of cloistered professor Bertram.
* VerbalTic: Sugarpuss' clicking of her tongue. Becomes an IronicEcho at the end of the movie when the professors do it.
* WilliamTelling: The protagonist's professor friends get a gangster to stay seated in a chair by challenging him to hit a coin held by one of them in his fingers.
* ZipMeUp: Sugarpuss asks the professors to zip up her skirt. Consternation predictably ensues.