'Pretty Little Liars' wardrobe designer Mandi Line admits that the upcoming Halloween episode of the thriller series made her nervous. Line says that viewers are very excited to see the annual costume extravaganza of Ravenswood so that they can draw inspirations from the characters.

"Until this show, I never got nervous about what fans thought. Come mid August or early September [every year], I start getting Facebook messages and tweets like, 'What's it going to be? Give me a hint! I want to prepare my Halloween costume.'" reveals the designer.

The much-awaited episode will be airing this Tuesday, October 22 and viewers will finally have a glimpse of what Aria, Emily, Hanna, and Spencer will wear to the World War 2-themed soiree. The clothes have been created in less than 3 weeks.

Line says that it was a challenge to create costumes that have old-world glamour but still appealing to the young viewers: "I thought, 'Kids aren't going to get this,' then [creator] Marlene [King] pulled me aside and said, 'Make it true to the silhouettes, but please put your modern touch on it. So that's where you get the bright colors, the sexiness."

Each costume was likewise replicated in case of any wardrobe malfunctions. Since the girls will be attending a party in a cemetery, dirt is inevitable: "We had to have perfect [duplicates] because [the script said] we were supposed to see them walking into the party."