Upon returning to Agatha's and overhearing the phone conversation in the séance room, a timed sequence will start. Run back down the hallway and enter the kitchen. Grab the knife from the nearby table. Go across the hall and pry open the birdcage in front of you (you'll have to look in it to see the newspaper inside before you'll be able to pry it open). Once you've picked up the newspaper, the trophy will unlock.
Solution taken from PlayStation Trophies:
https://www.playstationtrophies.org/game/indigo-prophecy/tro...