Scraps of paper and digital data lead Castle and Beckett to a hidden camera site where the "attack" was recorded.
He sets a "paper" trap (or rather, a ) in the fridge.
Giant footprints at the scene lead Castle to believe Bigfoot is the culprit.
The killer is Professor Devlin , who murdered Anne to cover up the fact that he had harassed and killed her roommate years earlier. 🍳 Bonus Subplot: The "Fridge Ghost"
Anne Cardinal, dumped at an ER with massive claw marks on her face.
Her notebook contains details about her sightings and the locations she was monitoring in the woods.
In the Castle episode (Season 5, Episode 20), "paper" likely refers to the missing pages from a researcher's notebook or the scraps of evidence used to track the "Bigfoot" killer. 🧩 The Paper Evidence