Someone’s Watching Me!

The real stalker is Herbert Stiles, the building inspector. He used his position to access multiple buildings across the city and installed surveillance equipment in Leigh's apartment. His job gave him legitimate access to apartments, which he exploited to monitor residents.

Early in the film, Leigh receives odd phenomena like lights dimming on their own, hinting that someone has access to her apartment's electrical system.

Police arrested a man based on Leigh's description and his presence in the building across from hers, but he was not the actual stalker. The man denied involvement and, frustrated with the investigation, left California to return to his native Iowa. The real stalker, Herbert Stiles, had manipulated events to redirect suspicion toward this innocent man.

Leigh spots a different man spying from a balcony after the first arrest, revealing the police apprehended the wrong suspect.

Sophie is attacked in Leigh's apartment while Leigh confronts the stalker. When Leigh returns, Sophie has vanished. Police later state Sophie had a flight to Fort Worth that night, but this explanation is presented ambiguously, her sudden departure without saying goodbye and the circumstances of her attack leave her fate uncertain.

Sophie watches from Leigh's apartment during the confrontation, but when Leigh enters the stalker's flat, she discovers Sophie being attacked in her own space.

As a building inspector, Stiles had authorized access to apartments throughout the city. He used his position to install microphones and recording devices in Leigh's unit without her knowledge. When Leigh breaks into his house, she discovers numerous surveillance devices confirming he had been monitoring her across multiple locations.

The strange phenomena in Leigh's apartment, lights dimming on their own and muffled phone calls, indicate someone has access to her living space.

The typewritten suicide note signed with Leigh's name is part of Stiles' final attempt to frame her or escalate the psychological terror. When Leigh returns to her dark apartment and finds this note, it creates maximum psychological impact, making her appear suicidal or making it seem like she orchestrated the events. Stiles then attacks her in the darkness, attempting to throw her off the balcony.

Earlier, the stalker sent anonymous gifts and letters that manipulated Leigh's sense of reality.

The Excursions Unlimited letters offering a free European vacation were part of the stalker's campaign to manipulate and intimidate Leigh. The letters created a false sense of opportunity while the stalking intensified, making Leigh question what was real. Leigh eventually follows the letter sender into the basement laundry room, where she hides beneath a drain grate while a man stands over her hiding spot.

The first letter arrives early in the film, coinciding with anonymous calls and the unlocked door incident.

Officer Gary Hunt explains that at that point, the stalker had not committed an actual crime, the surveillance and anonymous contact, while terrifying, did not yet constitute a prosecutable offense. This legal limitation frustrated Leigh's efforts until the situation escalated dramatically. Even when police did act, they arrested the wrong man.

The police visit occurs after Leigh, Sophie, and Paul set up their own stakeout using a telescope to identify the stalker.

A late-night phone call reveals the stalker knows intimate details about Leigh's life, prompting her to realize the man she observed through a telescope in the building across from hers is the one watching her. She connects the dots that the stalker is using a telescope to peer into her apartment from the opposite building.

Early in the film, Leigh receives anonymous gifts including a telescope, sent by the stalker, establishing the tool's significance.

Leigh arms herself with a walkie-talkie and a knife, then heads to confront the stalker while Sophie watches from Leigh's apartment. She manages to enter the stalker's flat but discovers Sophie has been attacked in Leigh's own unit and has vanished. Leigh rushes back to find Sophie gone, then continues the investigation that leads her to Herbert Stiles.

The stakeout with Sophie and Paul was a precursor to Leigh taking direct action.

After uncovering a hidden microphone in her apartment, Leigh and Paul investigate further and learn that building inspector Herbert Stiles has access to numerous buildings in the city. They connect his official position to the surveillance. Leigh then tracks down Stiles' address and breaks into his house, where she finds a collection of microphones and surveillance devices confirming he has been bugging her place.

The hidden microphone discovery in Leigh's apartment is the key evidence that points toward someone with authorized building access.