A horror and police procedural trope where the police set up a phone trace to catch a criminal but they need them to stay on the line for a certain amount of time. The amount of time will vary, yet somehow the criminal will know the exact amount of time and purposely hang up just before the police can get a trace. If it's a particularly high-tech setup, expect to see a computer generated map showing the tracing process.
Even if the person on the other line is encouraged to keep the other person talking, it never seems to work. The criminal will say everything they want and still always hang up a few seconds shy of the minimum time to trace the number. In some cases, the criminal will say they're aware of the phone trace or say how many seconds the call took. This trope is often used by serial killers or any particularly clever character. A common subversion is to stay on the line just long enough for a trace, but the purpose is to lead the police somewhere else as part of the criminal's elaborate plan.
Up until perhaps the late 1970s and early 1980s this was somewhat accurate. Telephone switches were racks of mechanical switches in which, when you dialed a number - using a rotary phone, a line selector used the clicks to determine which frame in the next digit to connect your call to. You dialed a 3, and the relay went to the 3xx-xxxx rack, then the next digit of 7 would connect to 7 rack in the 3 series, and so on, until you got to the last digit of the subscriber's number. If it was in use, you got dumped to the busy generator. Otherwise, you got to hear the ring tone as the line was rung. All these connections were created to make a physical connection between your phone and the destination phone. That means, to trace a call on a mechanical switch, they had to see where the wire ran to, then trace what that one was connected back to. This also meant, if the trace wasn't finished before the call was, the "sickening sound" of a call collapsing as the circuit was released for another call to go through.
If the call was long distance, they'd have to send someone to the central office that connected the call to the city, then trace it back to wherever it was connected from, and so on. This is why if someone was making obscene phone calls long distance, it would require many repeated calls to trace back the caller because of the time involved to trace, say, a call over mechanical switches from Pasadena, California to Ellicott City, Maryland. However, traces from major cities (say, Los Angeles to Baltimore or Chicago) even over mechanical circuits would be much faster, because the calls didn't have to go through intermediate cities.
As digital computers became more powerful, a switch basically was a mainframe computer with a bunch of phone lines plugged into it instead of a bunch of racks connected by mechanical relays. As a result, tracing a call means nothing more than going to the console, entering the phone number and asking who is connected to it. Eventually with the development of SS7 switches, it got to be sophisticated enough you could get it yourself in real time for a few dollars extra through Caller ID.
An essential part of The Calls Are Coming from Inside the House.
As technology marches on, this trope has morphed into tracing the computer connection, but the essence remains the same. Is often a source of artistic license, since (unless the work is set in the 1960s or earlier) the phone company can use their computer records to tell the cops what numbers called a given phone, and when, even months after the call.
Not counting Caller ID, which landline phones can get at a fee, and which is included on cell phones as part of the service, giving you the caller's number (and possibly name) before you even answer the phone.
In order to justify this trope in a modern day setting, the call is often bounced through a bunch of alternate locations, and the back-tracing of the call to its actual source will take time.
- In The Lost Experience DJ Dan gets a call that turns out to be from Rachel Blake (using her hacker alias, Persephone). He tells his cohost Tanya to trace the call and she says "Trace it? With my pencil?"
- Averted, but played with, in K, when the main character Yashiro Isana, who has been framed for a murder, calls Scepter 4, the local supernatural police unit, to tell them who he thinks might actually be responsible, they trace the location of his cell phone. He's in a truck on a bridge, and a group of officers go to catch him, but he manages to get away before they pinpoint which truck he's in. He leaves a piece of computer hardware in the back to make them think he was proxying the call from somewhere else and cover the fact that he simply got out of the truck, into a boat on a nearby river.
- Bookhunter has a variation where a perp is using a phone line to hack a computer. The cops are able to get the number the hacker is calling from easily enough, but it's a public phone booth, so they must race to physically apprehend the cracker and they don't have any way to keep the perp on the line longer.
- Vanko hangs up before Tony can finish tracing his call in Iron Man 2.
- Seen in Hackers, where the heroes specifically set up the phones to mislead the FBI as to their location. They know it won't last, but they delay as long as they can.
- In Sneakers, the heroes set up this elaborate multi-hub "fence" between their call location and the NSA before calling the government agency in order to negotiate for the MacGuffin. In the space of three minutes the NSA trackers are almost at their door, but they manage to disconnect before they are discovered... or so they think.
- The Federal Marshals tracing Richard Kimble's call in The Fugitive. A subversion because Kimble wanted them to trace the call to the real killer's house; he just puts down the phone without hanging up.
- Similarly subverted in the first Mission: Impossible movie, when Ethan Hunt stays on the line just long enough for his call to get traced to London (but not to the specific address) just as planned. Down to the second, even. The person he was speaking to realizes that someone of Ethan's skill wouldn't have allowed them to track him down unless he wanted them to. Ethan is a fugitive, having been branded a traitor. Having just found the real mole, he wants the IMF to catch them.
- Among the better known horror flicks to use the The Calls Are Coming from Inside the House twist, the original Black Christmas (1974) features quite a lot of effort on the part of the police force trying to get the lunatic killer who likes obscene phone calls to stay on the line so they can get a trace.
- In Air Force One, when the President calls the White House from a staffer's mobile phone, the White House operator naturally assumes it is a prank call...until the President tells her to trace the call and note it is a staffer's phone.
- Used in Goldeneye to figure out where Trevelyan's base is located.
- In The Bourne Supremacy, Jason Bourne speaks to Pamela Landy on the phone, and hangs up before they can trace his location. However, what he says before hanging up makes them realize he's directly in the area.
- Subverted in In the Line of Fire, in that the bad guy stays on the line for quite a long time. The trace goes through, but to the wrong location.
- Hopscotch: "Follett couldn't pinpoint his own backside in broad daylight!" A subversion, in that Kendig wanted the Feds to stop by and destroy his former boss' summer home. "I figure you've had enough time to trace this call so I'm hanging up now."
- Set up in Red: Cooper is encouraged by the tracer to keep Frank Moses on the line, prompting Cooper to string out the conversation. Frank was calling from Cooper's house and had made the call specifically to allow a complete trace to reveal that fact to Cooper.
- Three Days of the Condor. The CIA thinks they've traced Turner's whereabouts, but Turner has stolen a phone linesmen's kit and wired fifty phones together.
- Juggernaut. The police are shown racing to where the call from the bomber is coming from, only to find a bunch of public phones wired together.
- Memorably happens at the beginning and end of The Matrix. In the opening, Trinity stays on the line too long and is chased by Agents for her troubles. At the end, the trace program freezes midway through its run as Neo exerts his powers over the Matrix.
- In High and Low, police are trying to trace the kidnapper via this method.
- Played with by the villain in Die Hard with a Vengeance.
- The Silence of the Lambs. After Hannibal Lecter escapes he calls FBI agent Clarice Starling. During the call he tells her "Don't bother with a trace, I won't be on long enough."
- In the hacker movie Who Am I this is done with IP addresses. The Special Task Force manages to locate the heroes at a Berlin State Library and rushes over to catch them red-handed but arrive too late.
- Dredd has a villainous use where Dredd broadcasts an "I am the law" speech to Peach Trees and Ma-Ma lets him do so, in order to trace his location.
- Serenity. After the Operative has several of the Serenity crew's havens destroyed he talks to Captain Mal on the Wave (FTL radio). During the conversation Mal tells the Operative they won't be talking long enough for a Wave trace (which would allow the Operative to locate them) and turns off the communications device.
- In 12 Rounds, villain Miles Jackson is quite savvy to this, so he keeps hanging up and switching to a different phone every few minutes, frustrating the police.
- WarGames. After David accidentally hacks into NORAD and takes over its main computer system, he hangs up before they can trace the connection and determine his location. When the A.I. computer calls David back, the FBI manages to trace the calls and find him.
- Subversion in The Seekers, a drug dealer is mocking the bounty hunter company of the title, who picked up his slip after the dealer jumped bail. The dealer goes on about how the company will never catch him, because no one else ever has. But one day the leader of the Seekers opens his phone bill and finds an ad for a new service -Caller ID. The next time the dealer calls and brags (and brags and...), it takes about a minute for the number to pop up. Of course, it's never that easy.
- The same general set-up is used in Shatterpoint, albeit for a radio transmission rather than a phone call, with Mace Windu trying to keep the villain talking while his aide triangulates the signal source. However, because the villain is very clever and Mace is only slightly less clever, he immediately knows that the apparent origin is a ruse — but that still helps him because only two installations in city have the hardware necessary to spoof the signal.
- In one episode of Murdoch Mysteries, Constable Crabtree invents phone tracing.
- Happens all the time in Law & Order: Special Victims Unit, but it was a plot point of an entire episode. In "911", the squad gets a call from a 9 year old girl who says she's locked in a room, she's been abused, and does not know where she is. Olivia stays on the line with her and works with the squad to try and narrow down the area to where the girl might be being held. The number itself is untraceable, but a tech expert in cell phone mapping is eventually able to narrow down the cell phone tower the girl is using.
- The X-Files:
- In the episode "Pusher", Mulder and Scully try numerous times to trace Modell's call, but cannot. The "countdown" aspect is even more sinister in this case, because in one instance, Modell induces a heart attack in the lead agent and hangs up seconds before the call is traced.
- In "Beyond the Sea", the investigative team prepares to trace a call because they expect that a convict on a Death Row who claims is a psychic and might help them save two teenagers from torture and death. They think he's phony and that the kidnapper is his accomplice. They suppose he will call him, instead, however, he calls Mulder's mobile phone. It's never explained how he got to know Mulder's number.
- In "Lazarus" a suspect keeping Scully hostage calls the FBI to demand a ransom. Mulder keeps him on the line long enough, but the suspect was smart enough to use Scully's cell phone, making the trace useless.
- Happens in Muppets Tonight where a pair of crewman trace the call... by methodically ripping the phone cable out of the walls.
- In an episode of the Brit Com Nelson's Column, The Ditz gets a call from the police telling her that she's about to get a Harassing Phone Call, and she needs to keep him talking so they can trace the call. A few minutes in, Nelson asks how the police are supposed to have known this, and she looks blank for a second, then hangs up.
- In the NCIS: Los Angeles episode "Burned", the team attempt to trace a cell phone call to Callan. The guy on the other end is good enough to cut the call off when they triangulate it to within a block of his location.
- On an episode of Diagnosis: Murder, the killer who had previously dodged phone traces allows the call to be traced to a pay phone to distract the police.
- Beautifully subverted on an episode of Wire in the Blood. The police are getting phone calls that the tech people can't trace to anywhere at all. Detective Jordan correctly deduces that the perp must be a phone engineer, and they find him all the faster for it.
- Lost had an episode in which Kate called the police from a phone booth, with a clock set to remind her of the seconds she had before they could track her.
- Attempted in one episode of Police Squad!. The call is ended before the trace is completed, and when they show the phone that they had 'tapped', there is a faucet attached to the handset. Drebin's attempt to keep the kidnapper on the line long enough included asking "If a train leaves Chicago going sixty miles an hour and a train leaves Detroit..."
- Hawaii Five-0: The long running original series had a few instances showing what was required to run a trace, namely someone at the central office to run around and literally trace the connection. On one occasion Five-0 was able to anticipate a call and have people in place to run the trace faster.
- Seen quite often on 24. However, this show often averts it from the norm by them being able to get at least a partial trace even if they weren't able to narrow down the exact location before the disconnect.
- On "Redacted" on The Mentalist, the team acquired a dead man's cell phone, which one of their suspects was calling. They said it would take two minutes to triangulate the call. Patrick Jane took the phone, named a location and issued an ultimatum, then hung up. When everyone looked at him askance, he said that it would just be easier to bring the suspect to them. He was right.
- Played perfectly straight on The Following, despite the show's airing in 2013 and apparently being set in the present day.
- Dragnet and Adam-12 have both used this on occasion to find victims, such as potential suicide cases who've called somewher and got disconnected.
- In "Mr. Monk and the Missing Granny," though the police set up a wiretap when the guys who kidnapped Julie Parlo's grandmother call to give their ransom demand (free turkey dinners for all the homeless people in the Mission District), the kidnappers apparently know about the 45 second trace rule and hang up partway through.
- In "Mr. Monk and the Really, Really Dead Guy," the 'Six Way Killer' calls the police station to taunt them. Stottlemeyer tries to stall the guy, but midway through the phone trace, though, wires get crossed because Monk is intercepting an email from one of Julie's friends. This results in the SWAT team accidentally busting a slumber party instead. Naturally, Agent Thorpe is furious with Monk for this mistake. In real life, switching a few cables would not cause a mixup in a phone trace.
- Forever Knight: One episode had a serial killer phoning a radio psychiatrist, and killing his victims on the air; he knew about phone tracing, and was keeping his calls short enough to prevent a trace. He also specifically called from a public phone when he expects them to be running a trace for this reason. When he kidnaps the psychiatrist, Nick takes her place on the air, and starts playing mind games with the killer so that he stops watching his clock and stays on the phone too long.
- MacGyver - The villain in the 1990 episode "Lessons in Evil" manages to beat a trace at one point.
- In the Midnight Caller episode "Twelve Gauge," a man calls the station to talk about his plan to kill his ex-girlfriend and himself. He hangs up when he realizes he's being traced, but Jack is able to talk him into calling again.
- The aptly named Trace Tracker program in Uplink provides a very stereotypical depiction of this trope, as befits the game's Extreme Graphical Representation of Hollywood Hacking.
- Batman: Arkham City has Batman using the bat-computer to trace the phone calls he gets from Victor Zsasz. Bonus points since the missions actually involve racing as well - Batman has to race across the city to another public payphone each time in order to prevent Zsasz from killing a random person. Zsasz is actually careful enough to never stay on the phone long enough each time to be traced, either, but Batman can build up enough detail from his repeated calls to eventually find his lair.
- There's another justification for this - Zsasz is actually bouncing his phone signal around the network, making it harder to pin-point where the signal is coming from (it's implied that the Riddler is helping him).
- In PAYDAY 2, the premise is played with - instead of police trying to find a criminal, it's criminals trying to find another criminal. In the Hotline Miami mission, you have to destroy the property of a Russian mob boss you're targeting to make him angry enough to call and insult you. During the calls, Bain runs a trace to try and track down his location. The boss hangs up several times during the traces, requiring you to do more damage to get him back on the line. It's ultimately downplayed, as while the trace successfully narrows the search down to a region of a city, you have to find more clues to get the boss's exact address.
- Invoked in the Real Trailer, Fake Movie The Waldo Ultimatum.
- Cracked's references to misconceptions about it.
- One victim of Minnesota Burns tells him to keep talking so he can track him to his address.
- The Archer episode "El Secuestro" has ISIS trying to keep Pam's kidnappers on the phone long enough to trace the call (and usually failing, due to Archer or Malory's tactics). The two minutes needed to trace the call is lampshaded by Gillette, who says Malory cut money from the tracing program to pay for her new conference table.
Malory: Guess how many pygmies died to build this table. I'll give you a hint: six.
- The Perils of Penelope Pitstop episode "The Boardwalk Booby Trap" has Penelope trapped in a phone booth headed for a fish cannery, so she calls the Ant Hill Mob (Pockets answers with a phone in his jacket) which leads to the "You don't say!/She didn't say" gag. Clyde tells Zippy to trace the call to see where Penelope is. Zippy does so by entering the phone itself and traversing the phone line to Penelope's booth.
- The Simpsons: Mr. Burns' son Larry fakes abduction to make Burns show his love. When the "kidnapper" calls, Chief Wiggum does trace the number but, upon reading "555", dismisses the number as a fake.
- Dick Tracy gets a phone call from Stooge Viller saying that he and Mumbles have kidnapped the Retouchables (Hemlock Holmes' crew of police officers) for ransom. Tracy patches the call to Hemlock via their two-way wrist radios and somehow Hemlock is able to trace where the call came from.
- The non-fiction book The Cuckoo's Egg has a fairly detailed account of what it took to trace an international data call in the late Eighties. The author, Clifford Stoll, set up a honeytrap to try keep a hacker on-line long enough to trace. This would later become unnecessary, as phone companies and government agencies were able to perform something called a "lock-in trace," which kept the line from hanging up until the trace was complete.
- An example of how television could be killing us - if calling 911 from a cell phone, don't count on them simply being able to do a quick trace and find out where you are. In fact, as of February 2015, a USA Today report indicated that your odds were about 50/50 at best.