Pretty Little Liars Season 1 Episode 18 : The Bad Seed

The girls are doing a play together; while done rehearsing, they find a trophy with blood on it, making them think its Alison's blood... but it turns out to be rat's blood; they all revisit memories about when they crashed a frat party; Aria uses the play to get closer to Mr. Fitz; Hanna and Caleb kiss; the police come after the girls at the end with some questions.