Gotham’s Ivy Pepper is sprouting like a weed!

“She is a big girl now,” confirms executive producer John Stephens. The character, first played by Clare Foley, will morph from misfit tween into a spicier Pepper (Maggie Geha, above, and her DC Comics counterpart, Poison Ivy, left) when the Fox drama returns on September 19.

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“One of the creatures that escaped from Indian Hill [in May’s finale] has the power to age people,” Stephens says. “Sometimes he uses it to kill people; other times he doesn’t get to complete the process.”

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But Gotham hasn’t forgotten Ivy’s roots. Stephens says the change from Foley to Geha feels organic. “Maggie really seems like Clare. She is playing the same intonations and rhythms. It’s great.”

Gotham, Season Premiere, Monday, September 19, 8/7c, Fox.