Jonny Lee Miller as Sherlock, Lucy Liu as Watson
Sherlock (Jonny Lee Miller) and Watson (Lucy Liu) investigate a crime detected by a cutting edge technology called Bullet Point in Season 5, episode 17 of “Elementary.” CBS

Sherlock (Jonny Lee Miller) and Watson (Lucy Liu) find themselves looking into a gunshot detection system called Bullet Point when the said cutting edge technology recorded the audio of a crime.

In a sneak peek from Season 5, episode 17 of “Elementary,” Captain Gregson (Aidan Quinn) brings Sherlock and Watson to the location where Bullet Point recorded the audio of the crime.

“In an hour and half ago, it picked up multiple shots in this corner,” the captain tells the pair. “It also recorded the voice of the shooter. He was torturing someone for info. He wanted to know where the guy had taken a woman named Francis.”

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Captain Gregson said that he’s not sure whether Francis was kidnapped, and that’s why he called Sherlock and Watson for help.

“According to Bullet Point, the shooting occurred right here. But when our guys arrived at the scene there was no blood, no slugs, no body,” Captain Gregson says, before pointing to vehicle tracks on the ground. “These tracks are fresh and that’s about all we got.”

Captain Gregson thinks that the shooting took place inside a vehicle which later drove away. This theory is confirmed by confirms during a meeting with the makers of Bullet Point and New York City representatives.

“I can vouch that the shooting took place where Bullet Point said it did,” Sherlock says in another sneak peek from the episode. “I found a shell casing a little further down the block. It likely fell from the vehicle that drove the crime scene away. Its odor confirmed that it has been fired recently, and its caliber matches the system analysis.”

Watson, who is also in the meeting, asks the makers of Bullet Point about how it actually works, and in the process finds out that the city is probably using the technology to gather information for its own interest.

“Our sensors listen for gunshots,” a female rep from the company who made Bullet Point says. “Once one is detected, then it begins recording all the audio for an agreed period of time. The arrangement with the city is ten seconds before the first gunshot until 30 seconds after the last one.”

When Watson asks whether Bullet Point is “bugging the city 24/7,” a male rep from the firm somehow confirms that it’s actually the case.

“It’s like your phone or any device that is voice activated by saying Siri or Alexa,” he explains. “They are all listening all the time because they need to know when we need them, but they don’t pay attention until we do. … Instead of [saying] Siri, the signal is gunfire, and by paying attention, it means saving the audio.”

When the female rep insists that all the recording is “done under the strict oversight of the city,” Sherlock sarcastically replies: “That’s okay then, because governments never abuse the surveillance of this city, do they?”

In addition to Sherlock and Watson locating the actual crime scene, the shooter, the shooter’s victim and Francis, the episode also sees the return of Shinwell (Nelsan Ellis), who wasn’t seen in the past two episodes of the CBS series. According to the synopsis, Sherlock and Watson become suspicious of Shinwell when he becomes the target of a drive-by shooting that reveals his involvement in an unsolved murder.

“Elementary” Season 5, episode 17, titled “The Ballad of Lady Frances,” airs on Sunday, March 19 at 10 p.m. EST on CBS. Watch the sneak peeks from the episode below: