Shemp tries to get into the room with the table blade, but it's locked. After attempting to leave through the front door, he turns and runs back down the hall. The same door is now open as evidenced by the light coming through the opening.
When Larry leaves to go look for the girl after they enter the house, he walks to the left. Moe and Shemp are standing together. In the next shot you can tell there is only a wall with a picture hanging on it and no hallway on the left.
The light bulb Larry turns off with his tie disappears in the next shot.
When Shemp is yelling "Moe! Larry!" he says the name Mary, meaning the woman they are trying to rescue, but the woman's name is Louise.