After four seasons of waiting, Pretty Little Liars Season 4 Episode 24 starts putting together the pieces of the big A mystery.

Alison tells her friends about her last night in Rosewood. She was trying to figure out who A was, but she wasn't able to do so knocked her out with a rock.

However, she did learn that her mother knows who tried to kill and try to bury Alison to cover it up. The girls are unable to figure out who A is before the masked figure shows up and begins shooting at them.

Fortunately, Ezra is there and saves the girl from A. But he meets a tragic fate.

Meanwhile, the Hastings are being questioned by the police because Spencer is suspected of killing the girl who's buried in Alison's grave.

Watch Pretty Little Liars online and see if you can figure out who A is.