He sets and springs a trap

Gun in hand, Frank padded downstairs in the dark. The window attempts were on one side of the house, and Frank decided to give whoever it was a surprise. He unlocked a side door of the house, found a place to hide, and settled down to wait.

Ten minutes later, there was a scrabbling at the door, and then the sound of the handle turning and the door opening. Frank could see a dim figure in the doorway and aimed his pistol at it, watching carefully. The figure stood still for a moment, then stepped in, closing the door behind them.

There was a little murmur, and then a dim light appeared, obviously coming from the screen of a phone. Frank was able to see the figure moving slowly, and hear their nervous breathing. He smiled and relaxed slightly, almost sure that the intruder was not a professional assassin but rather some adventurous teen.

He was waiting near the door to the stairs coming down to this room, which he had left open behind him. Another door, nearer to the intruder, led to a bedroom and ensuite bathroom. This area had been designed as a separate suite when the house was built, and besides putting the minimum of furniture in it, Frank never used it.

When he heard and saw the intruder open the bedroom door and enter, he slipped across the room and locked the outside door, then retreated up the stairs to wait, taking care to make no noise.

A few minutes later he heard footsteps and saw a dim figure at the foot of the stairs, lit only by their cell phone. When he saw that they had started up the stairs he grinned, pointing his pistol down as he flicked on the light to illuminate them.

There was a sudden frightened squeal and a scurry of footfalls, then a rattling as Patty Elston frantically tried to open the outside door. All of this Frank heard as he bounded down the stairs, and caught her, pressing her slender, terrified body against the door as he hissed in her ear.

"I told you, you'd come back. This is gonna be fun!"