"I'M ALICE ANGEL!"
The power hallway is a location and one of the many Level K rooms from Chapter 3 of Bendy and the Ink Machine. This is where the first Butcher Gang enemy, Piper, is encountered. It appears to be a breaker room, as apparent from the presence of power switches.
The hallway is connected between the toy storage and the entrance to Level K.
When Henry enters this location, he will need to pull both of the levers to activate the door at the same time. Henry tells Boris to get the one closer to the door, and then Henry goes to the other switch. Before he gets to the lever, Piper pops out of "The Butcher Gang" poster. Henry cannot pull the switch until he finishes Piper off.