1. The Pedant in Taming of the Shrew when Biondello hatches his plan.
    Biondello approaches a stranger and asks where he's from. "Padua," he says. "Ack! Don't you know the duke has declared that anyone from…uh…Padua is to be executed? But don't worry, I'll disguise you and keep you at my house so you'll be safe. You even look a lot like my dad." "Oh thank you," says the old man. And then Biondello says, "Hey by the way, my girlfriends dad is going to ask you to approve my marriage and gaurantee my dower. Pretend to be my dad and say ok." [WAIT A MINUTE]
  2. Juliet in Romeo and Juliet when Fryer Lawrence hatches his plan.
    "Here's an idea. You drink this potion and it'll basically make you die and then you can wake up in the tomb in the middle of the night and go be with Romeo." [WAIT A MINUTE]
  3. Sebastian in Twelfth Night when Olivia swears her love.
    Sebastian enters a town for the first time in his life and Olivia runs out to him. "Oh it's you Sebastian. I love you so much. How dare you leave me. Let's go to the church right now and get married." Sebastian's like, "it's a little weird but I'm going with it." [WAIT A MINUTE]
  4. Edgar (in disguise) when his blind father recognizes Lear's voice.
    Edgar's father has been blinded. Edgar pretends to be a crazy guy and leads him to what he thinks are the cliffs of Dover where the father "jumps". Edgar then pretends to be a *different* person at the "cliffs" and leads his father to safety. His father never suspects it's him. Then they bump into Lear and the father recognizes Lear's voice immediately. [WAIT A MINUTE]
  5. Titus Andronicus when Titus insists Tamora's sons stay with him while she goes to get Saturninus.
    Titus: "I'm totally insane and my life has been ruined by the person I totally keep saying you look like. Also I keep saying these guys look just like your sons who defiled and disfigured my daughter. Also I'm a huge war hero and my soldier sons are all around. Leave these guys here with me for reasons. I swear I won't hurt them. I'm like crazy and harmless." Tamora: [WAIT A MINUTE]
  6. Margaret in Much Ado when Borachio propositions her.
    Borachio: "Hey hottie remember me? Let's mess around." Margaret: "Totally." Borachio: "Let's do it in Hero's room for kicks." Margaret: "Totally." Borachio: "You should wear Hero's clothes too." [WAIT A MINUTE]
  7. Margaret in Much Ado when Claudio accuses Hero
    Claudio: "I saw Hero in her window last night wearing her clothes and messing around with some other guy. SLUT!" Everyone: "GASP!" Margaret: [WAIT A MINUTE]
  8. Hero in Much Ado when she learns the whole truth about Borachio, Margaret, and Don Pedro.
    Margaret: "It was me not Hero but I was too embarrassed to admit it so I let a marriage and like five lives get ruined lol." Leonato: "Oh silly Margaret! No harm no foul." Hero: [WAIT JUST A GOD DAMNED MINUTE]
  9. In The Two Gentlemen of Verona when Proteus tries to rape Sylvia
    Proteus: And love you 'gainst the nature of love,—force ye. Silvia: O heaven! [WAIT OMG IT'S A COMEDY!!)
    Suggested by @ChrisK
  10. In Richard III, when Richard makes a move on Lady Anne at her husband's funeral, who is Richard's brother, and who Richard himself killed... And she totally goes for it.
    (But it's nonetheless one of my favorite scenes of all time.)
    Suggested by @HeatherQuinn
  11. When anyone in Hamlet sees a ghost. This is Denmark, not an episode of Scooby Doo.
    Suggested by @lucas