Backup Twin/Playing With

Basic Trope: A character is killed but the actor returns as his hitherto unseen twin sibling.
 * Straight: Alex is Killed Off for Real. In the next episode, Alex's long-lost twin brother Bob is introduced and continues to play pretty much the same role.
 * Exaggerated:
 * After a Kill Em All, all killed characters are revealed to have long-lost twin siblings.
 * Or, the twin dies, and it turns out there were triplets...then the triplet dies and it turns out there are a whole ton of backup siblings.
 * Justified: Bob was innocuously mentioned or even introduced ten episodes earlier and other characters specifically seek him out and convince him to take over Alex's duties.
 * Inverted: Alex resurrects his Dead Little Twin Brother Bob, then takes a Long Bus Trip.
 * Subverted:
 * Bob is actually an impostor who took on Alex's appearance to infiltrate the circle of his friends.
 * Alternatively, It turns out that Alex has faked his death, and that Bob is actually him.
 * Double Subverted:
 * After getting to know Alex's friends, the impostor Bob decides to become the mask.
 * Alternatively, it turns out that Alex was Bob all along, got tired of acting like his twin, faked his death, and reappeared as himself.
 * Parodied: Alex seemingly dies but returns after Bob jumps in, kicking off a heated argument on who is the real Alex now.
 * Deconstructed: Alex's friends find Bob whose personality is nothing like Alex's, and an attempt to substitute him with Bob ends badly.
 * Reconstructed: Alex's friends find Bob whose personality is nothing like Alex's but he learns to do what Alex did in the group and they learn to like him for what he is.
 * Zig Zagged: Alex dies and is replaced by his twin sister as a favor to the actress playing his part.
 * Averted: Alex has no twin siblings.
 * Enforced: "But he signed a contract with us for the entire season! You can't just kill him off like that! Find a way to put him back in!"
 * Lampshaded: "Ah, you must be Alex's twin brother. Nice to meet you. I guess there's no need to tell you that He Didn't Make It."
 * Invoked: "He's Dead Jim." "Check his family records for any unaccounted for twin siblings."
 * Defied: Hearing about Alex's death, Bob blows town and is never seen again to avoid associating with whatever business Alex was in.
 * Discussed: "Sir, I know what you are thinking but if Alex did have a twin, don't you think he'd tell us?"
 * Conversed: "He is a main character, duh... at least, they didn't pull out a Disney Death."
 * Plotted A Good Waste: Alex died in a way that was noble and deeply affecting, so the audience views the attempt to "bring him back" in the form of Bob as a cheap trick which sullies their memory of the character.
 * Played For Laughs: Though physically identical, Bob is nothing like Alex, forcing the main cast to go to ridiculous lengths to cover for his mistakes and/or explain his changed personality to those who knew Alex well.
 * Played For Drama: Alex's girlfriend cannot accept Bob but is forced to appear together with him to maintain the secret of Alex's death.

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