As seen in Wednesday's episode, the Lazarus Pit has already begun to have serious effects on Thea (Willa Holland), who was only briefly dead before her resurrection. And since Sara has been dead for months, that means the Pit's influence on her will be far worse, something she will continue to deal with when she joins the spin-off Legends of Tomorrow in 2016.
"Her story is really a simple one. It's her trying to regain her humanity, trying to find a human connection," Legends showrunner Phil Klemmer says. "It's kind of this paradox that she's selected for the team because she's this ruthless, cold-blooded assassin and what she really wants is to feel again. And these two things are at odds."
But despite all the ways Sara will have drastically changed when she comes back from the dead, Laurel will continue to stand by her sister's side.
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