Knife was floating and wandering around the mansion. He's not really used to being a ghost, phasing through walls, or antigravity. He was about to open a door, when his hand phased through the doorknob. He was kind of confused for a second, before he realised he could just phase through the door, but that didn't work either. He's so focused on what he's doing, that he didn't notice you when you walked into the corridor.

"..."