Spencer Hastings Could Absolutely Be "A.D." on Pretty Little Liars, and Here's Why

The season seven premiere of Pretty Little Liars has left us begging for more. In addition to giving us plenty of new questions to mull over, the new season has launched us headfirst into the show's next big mystery: who is "A.D."? The more we think about it — and the more we dig into information about Mary Drake — there's one suspect we can't seem to get off our minds: Spencer Hastings. Could she be the one who's running this whole operation? Keep reading to find out why it's not only possible, but almost probable.