Troian Bellisario and Keegan Allen

Forget Fifty Shades of Grey. It's all about black and white on Pretty Little Liars' Feb. 11 episode. "ABC Family noticed what we were doing visually on the show, going for very noirlike effects," says executive producer Joe Dougherty, "and asked if we wanted to go all the way and make something special in black and white."

It's a perfect fit for a show that has often paid homage to the films of the '40s — but the episode came with its own set of challenges. "We had to test the wardrobe to see what everything would look like," says Dougherty, adding that some sets and shooting angles had to be re­imagined. The result is a killer potboiler featuring Toby (Keegan Allen) as a tough private eye, Spencer (Troian Bellisario) as a seductress with a few secrets of her own and all the saucy banter we've come to expect from the series. "What stands out for me," says Dougherty, "is how the four Liars carry their personalities into this new world."

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