4. Casablanca: Play it again, Sam.
Made famous by Humphrey Bogart and Ingrid Bergman, this love story was originally a play by Murray Burnett. The play was turned into a script by writers (and brothers) Julius and Philip Epstein and their friend Howard Koch. In the story, American Rick Blaine is the owner of a gambling club "Rick's Cafe Americain" in the Moroccan city of Casablanca. Set during World War II, Rick is a bitter man having been scorned by ex-lover Ilsa Lund. When she walks back into his life suddenly, now married, with her husband in tow, Rick is forced to come face-to-face with well-aged heartache.
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Fun Fact: In a 2005 poll by the American Film Institute, the Casablanca line "Here's looking at you, kid" was ranked the fifth most memorable line in cinema history. (Six other lines from the film are also in the top 100.)
5. Midsummer Night's Dream: Dream a little dream.
A romantic comedy by William Shakespeare, this play takes place in Athens as Duke Theseus plans a large festival around his marriage. During this time, Theseus' daughter, Hermia, is refusing to marry her fiancé. Due to a true-love-in-the-wings named Lysander. Against her father's wishes, she flees the nuptials for the woods. And guess who? While there, they befriend fairies who cause a bit of mischief. Cue a new love triangle and surprise ending!
Fun Fact: In the 1989 blockbuster film Dead Poets' Society, the character Neil Perry (played by Robert Sean Leonard), was cast as Puck in the a local production of A Midsummer Night's Dream.
6. Doctor Zhivago: Boy meets girl meets girl.
This Noble Prize-winning Russian novel by Boris Pasternak is the ageless classic of one man torn between two women. Yuri Zhivago is a medical doctor and poet during the 1917 Russian Revolution. While married to aristocratic Tonya, he falls in love with nurse Lara. Set during a war time, Zhivago's love triangle falls prey to a twist of fate, and becomes a tale of protagonist versus an achy, breaking heart.
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Fun Fact: Doctor Zhivago's first film version was a made-for-TV version produced in Brazil in 1959.