If you haven't seen the season finale of Pretty Little Liars, be warned: spoilers are ahead! Fans of the ABC Family show were in for one of the biggest surprises of the series on the last episode when it was revealed that Mona (Janel Parrish) — who we thought was long dead — was very much alive. We caught up with Janel as she teamed up with Pop-Tarts in honor of National Peanut Butter and Jelly Day to talk more about the stunning reveal. Watch us chat about just who Charles DiLaurentis is, why she hated going blond for the show, and the most outlandish theory about PLL she's ever heard.