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Tear Jerker: Romeo and Juliet
Possibly even sadder than the loss of the title pair is the fate of those who remain. Here's the Nurse, Lady Capulet and Lord Capulet, who loved Juliet so much. They've just lost Tybalt, the closest thing to a child they had besides Juliet. And, having already lost Juliet once (when they thought she was dead) they have to go through the pain all over again, knowing that they could have saved her if they'd only known, knowing that their poor, extremely young daughter spent the last moments of her life in pain and heartbreak. Lord Capulet has to live with the fact that, in one of his last conversations with her, he frightened and threatened her, expressing that he wished she had never been born, and that his actions probably were what drove her to fake her own death. The Nurse was in on the marriage, but didn't know enough to save Juliet. Then there's Lord Montague, who's all alone now that his wife and his only son are dead, and poor Benvolio, who (if he's even alive) has lost his two best friends... take it all together, this might just be the saddest ending in the history of literature.
Lord Capulet's reaction to Juliet's "death," before she actually does die. Yes, he acted like an ass, but how can you not feel sorry for him?
"My child is dead; And with my child my joys are buried."
The suicides. No matter how cliched you find it, no matter how much you hate the story, no matter how much you want to smack the leads, if your production's Romeo and Juliet are doing it right, they'll have at least a couple audience members in tears.
The French musical adaptation, particularly Roméo's song before his death:
It's over, I'm done
I wanted to know about life, now I know
I am so tired
I don't want anything but
To simply lie down, and take her hand
Put it on my heart, forget my pain
And Benvolio's song about having to tell Roméo about Juliette's death:
Yesterday, we were still
So far, so far from death
She's fallen on the village
Like a spider spinning her web.
The music as Juliet dies in the Zeferelli movie.
Mercutio's death in the Baz Luhrmann version.
In the Romeo+Juliet version, Juliet's reaction after seeing Romeo die in her arms. The long pause let out by a single sob. It's powerful.
A lot of people found it (the sob) incredibly narmy, as well as the fact that Juliet takes a good ten seconds before she reaches out and touches Romeo (although this could be interpreted as her still being woozy from the potion. See here.