Law & Order: SVU

While her warrior-like V character is fighting to save her only child from evil lizards, Elizabeth Mitchell is also playing another role — one kiddies should fear. The beloved Lost alum guest stars on Law & Order: SVU on March 30 as June, a piano teacher accused of killing a little girl after raping her with a rolling pin. It's pretty heavy stuff, which caused the real-life mom to take pause.

"I had certain things I was and wasn't willing to do — you never actually see anything," says Elizabeth, who played a different child killer on SVU back in 2003. "This is a hard one. You have to do your work, and then leave it behind before going home because it's absolutely toxic."

Things were much breezier off set, where Elizabeth's 5-year-old, Christopher, made a new BFF in Mariska Hargitay's son, August, 4. Says Elizabeth, "They got to play and it was the sweetest thing I've ever seen."

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