The Witness Who Was Never in the Room
Black Mirror's Icelandic murder spree invents a machine that plays your memories on a screen. The machine is decades off. The idea buried inside it, that memory is a draft and not a tape, is the part worth keeping.
Nearfi scores Black Mirror: Crocodile (2017) 6.6/10 as art. Andrea Riseborough and John Hillcoat's snowbound Nordic-noir look give a cruel story real chill, and the Recaller's blurry, suggestible memories are a smart design choice. As prophecy, its P(n) is 64%: Nothing can play back a remembered scene, but insurers mining personal data, driverless vehicles on the street and investigators coaxing witnesses with cues are all already here.
- Andrea Riseborough and John Hillcoat's snowbound Nordic-noir look give a cruel story real chill, and the Recaller's blurry, suggestible memories are a smart design choice.
- The killings escalate until the plot is a chain of coincidences, and the final twists feel more like a bet than a conclusion.
- Unlike the grain of "The Entire History of You", this memory machine is fallible, which is closer to how recall really works.
Nothing can play back a remembered scene, but insurers mining personal data, driverless vehicles on the street and investigators coaxing witnesses with cues are all already here.
- NEAR A device can reconstruct the images in a person's visual memory and play them on a screen.
- ARRIVED Insurers investigating a claim draw on witnesses' and claimants' personal data, and people routinely let them.
- ARRIVED Investigators use smells, sounds and prompts from the scene to strengthen a witness's recall, and know that suggestion can change what the witness remembers.
Nothing can play back a remembered scene, but insurers mining personal data, driverless vehicles on the street and investigators coaxing witnesses with cues are all already here.
Mia Nolan has just killed a man in a hotel room, and the first thing she does is the wrong thing. She looks out of the window. Across the street a self-driving pizza truck is running down a pedestrian. Mia has now committed a murder and seen a crime. The second will be what undoes her.
"Crocodile" is the third episode of series four of Black Mirror, written by Charlie Brooker and directed by John Hillcoat. It is 59 minutes long, arrived on Netflix on 29 December 2017 with the rest of the run, and is set in Scotland though it was filmed in Iceland. Spoilers follow, and they are not gentle.
The art: Nordic noir with a sat-nav
Andrea Riseborough plays Mia, an architect who, fifteen years earlier, helped Rob dump the body of a cyclist he had hit while drunk. Now Rob is sober and plans to send the dead man's widow an anonymous letter. Mia fears it can be traced, and breaks his neck. The episode is a slow-motion pile-up from there. Kiran Sonia Sawar plays Shazia, an insurance investigator working the pizza-truck claim, who uses a handheld device called the Recaller to view witnesses' memories of the crash. Mia never meant to be a witness, and the Recaller is how she is found.
The look is magnificent. Hillcoat and the cinematographer Lol Crawley shoot Iceland as a country made of fog, glass and mountains with the sound turned down. The weather does a lot of the work. The episode often looks as good as anything in the series.
Riseborough is better than the script. She plays Mia as someone who is not a monster but a person who keeps making the next reasonable decision, which is the scariest sort. Sawar's Shazia, a tired professional hoping for a bonus, is the best thing in the middle hour, and the episode treats her death with an awfulness it has earned.
Then it keeps going. Mia's killing spreads to Shazia's household, and the last witness the police can find is a pet guinea pig. It is played as black comedy, and it does not land for me, and plenty of critics said the same. The pile-up becomes arithmetic. Each murder is the previous one's receipt. Rotten Tomatoes sits at 53%, which sounds about right for something so good-looking and so cold.
The prophecy: one machine, three accomplices
The Recaller. A box that plays your memories on a screen. We are a long way from that. Researchers can rebuild, crudely, the pictures a person is looking at from fMRI scans, and a 2023 decoder at the University of Texas at Austin recovers the gist of heard or imagined stories. Both need a scanner, hours of training on one person and that person's cooperation; untrained people and people who think about something else produce nothing useful. Nobody can read a remembered scene out of a head. Call it 2075, with a wide range either side.
The memory itself. Here the episode is far more intelligent than its gadget. The Recaller shows what a witness can picture, not what happened, and it is not a recording. A witness's memory changes after someone mentions the colour of a woman's jacket. Shazia feeds witnesses sensory cues, a smell or a snatch of music, to bring the scene back. This is nearly the cognitive interview, developed by Geiselman and Fisher in 1984, in which a witness mentally reinstates the setting to help recall. The misinformation effect, studied since the 1970s, shows that later information can make a recollection less accurate. The 2014 US National Academies review of eyewitness identification recommends safeguards for how police and courts use such evidence. Brooker's trick is to make the machine inherit these flaws. The writer of "The Entire History of You" imagined perfect playback, and the lesson was that a perfect record ruins a marriage. Here, imperfect playback is the lesson, and it is the more accurate guess.
The insurer. Shazia works for an insurance company, and visits people who owe her nothing. Claims investigators do use social media, public records and vehicle telematics to test what claimants say, as a 2016 Milliman piece explained, while noting that checking every claim is costly. The Recaller is a fantasy. The reflex behind it, that a payout justifies a look into your life, is real.
The truck. A driverless delivery vehicle hits someone on the road. Toyota showed an autonomous e-Palette delivery concept with Pizza Hut in January 2018. The genuine article is robotaxis: Waymo does about 400,000 paid driverless rides a week in six US cities, according to a February 2026 report. In October 2023 a Cruise robotaxi dragged a pedestrian in San Francisco, after the person had been hit by another car, and California suspended the company's driverless permits. The episode's fear of the unaccountable vehicle was only slightly ahead of schedule.
The reading
As cinema, 6.6. Superb surfaces and a lead performance that deserves a better script, undermined by an escalation that runs on coincidence and a final act that reads as a dare. As prophecy, the machine is too far off to count but the bones are right, so it earns a NEAR. The best idea is the unflashy one. If recall is a reconstruction, a recording of it is a testimony, and testimony needs cross-examining.
Mia was undone by a stranger's memory of a street she barely noticed, which is the oldest point about witnesses and the newest about machines.
What it predicted, and what happened
The Recaller, a device that plays a person's visual memories on a screen, has no credible near-term path. The world around it is already here: insurers mining personal data, driverless vehicles on public streets, and investigators who know recall bends under suggestion.
How this P(n) was calculated
P(n) is the chance that this work's future arrives within 20 years, by 2046. For each prediction we turn our estimate into a probability: arrived is 100%, diverged is 0%, and otherwise the low end of our 80% range counts as a 10% chance, the median year 50% and the high end 90%. Each prediction is weighted 1–5 by how pivotal it is to the story, and P(n) is the weighted average. P50 does the same by 2076. P(n), explained.
| Claim | Prediction · why this weight | Weight | Status · estimate | By 2046 | By 2076 |
|---|---|---|---|---|---|
| CROC-1 | A device can reconstruct the images in a person's visual memory and play them on a screen. Core premise: the Recaller is the engine of the plot, and every murder is exposed by it. |
5 | NEAR 2075 (2055–2110) | 7% | 51% |
| CROC-2 | Insurers investigating a claim draw on witnesses' and claimants' personal data, and people routinely let them. Supporting: it explains why Shazia is at the door and why witnesses open up, but the plot would survive a police detective instead. |
3 | ARRIVED arrived 2016 | 100% | 100% |
| CROC-3 | Driverless vehicles operate on public roads, carrying goods or passengers, and sometimes hit pedestrians. Texture: the pizza truck's collision gives Mia a witness-in-waiting, but it is a coincidence the plot could have swapped for another. |
2 | ARRIVED arrived 2023 | 100% | 100% |
| CROC-4 | Investigators use smells, sounds and prompts from the scene to strengthen a witness's recall, and know that suggestion can change what the witness remembers. Supporting: the episode's best idea, that replayed memory is unreliable, drives its scenes of witnesses, but the plot turns on the Recaller itself. |
3 | ARRIVED arrived 1984 | 100% | 100% |
| P(n) = P20 = Σ(weight × chance by 2046) ÷ Σ weight = 8.3 ÷ 13 = 64% | |||||
| P50 = 10.6 ÷ 13 = 81% | |||||
Already here today (arrived 1, arriving ½, weighted): 62%.
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CROC-1
A device can reconstruct the images in a person's visual memory and play them on a screen.
Weight 5/5 · Core premise: the Recaller is the engine of the plot, and every murder is exposed by it.
Researchers can reconstruct what someone is looking at, crudely, from fMRI scans, and decode the gist of imagined speech. Both need a scanner, hours of training on that individual and a cooperating subject. Nothing reads out a remembered scene, and memories are reconstructions rather than recordings, so any such device would give a best guess. 123
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CROC-2
Insurers investigating a claim draw on witnesses' and claimants' personal data, and people routinely let them.
Weight 3/5 · Supporting: it explains why Shazia is at the door and why witnesses open up, but the plot would survive a police detective instead.
Claims investigators check social media, public records and vehicle telematics for evidence that contradicts a claim. That is far short of reading a mind, and insurers weigh the cost of checking every claim, but the practice of mining personal data to settle a payout is established. 456
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CROC-3
Driverless vehicles operate on public roads, carrying goods or passengers, and sometimes hit pedestrians.
Weight 2/5 · Texture: the pizza truck's collision gives Mia a witness-in-waiting, but it is a coincidence the plot could have swapped for another.
Waymo carries paying passengers with no driver in several US cities. Cruise's robotaxi dragged a pedestrian in San Francisco in October 2023 and lost its California permits. Delivery-specific vehicles are less common; Toyota and Pizza Hut showed a concept in January 2018. 789
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CROC-4
Investigators use smells, sounds and prompts from the scene to strengthen a witness's recall, and know that suggestion can change what the witness remembers.
Weight 3/5 · Supporting: the episode's best idea, that replayed memory is unreliable, drives its scenes of witnesses, but the plot turns on the Recaller itself.
The cognitive interview, developed from 1984, has witnesses mentally reinstate the setting to aid recall. Research on the misinformation effect shows later information can distort memory, and the US National Academies' 2014 review of eyewitness identification recommends practical safeguards. The episode's beer smell, passing song and a changed jacket colour use real principles. 101112
- FOR Semantic reconstruction of continuous language from non-invasive brain recordings. Nature Neuroscience, 2023-05-01. A non-invasive decoder rebuilds the gist of heard or imagined stories from fMRI.
- AGAINST Brain activity decoder can reveal stories in people's minds. University of Texas at Austin, 2023-05-01. Needs fMRI, extensive training per person and the person's willing cooperation; captures meaning, not exact words.
- AGAINST Tech demo takes brain scan, creates a picture of what you're looking at. The Register, 2023-03-07. Viewed images rebuilt from fMRI; it needs a scanner and about an hour of lying still.
- FOR Insurance fraud and social media. Milliman, 2016-07-20. Claims investigators search social media for evidence against claimants; posts count as public unless restricted.
- FOR 5 ways to fight insurance fraud with social media. Digital Insurance. Describes investigators combining social media, public records and telematics to test claims.
- AGAINST Insurance fraud and social media. Milliman, 2016-07-20. Warns that checking every claim this way is costly and could slow payments, so it is used selectively.
- FOR Waymo co-CEO Outlines Path to 1 Million Weekly Trips in 2026. Claims Journal (Bloomberg), 2026-02-12. About 400,000 fully driverless, fare-charging rides a week in six US cities.
- AGAINST CPUC pulls Cruise robotaxi permit after DMV suspension. TechCrunch, 2023-10-24. California suspended Cruise's driverless permits after a pedestrian was dragged.
- CONTEXT Crocodile (Black Mirror). Wikipedia. Records Toyota's e-Palette and Pizza Hut's delivery concept in January 2018 and the show's reply.
- FOR Cognitive interview. Wikipedia. Developed by Geiselman and Fisher in 1984; uses mental reinstatement of context to improve recall.
- AGAINST Misinformation effect. Wikipedia. Later information can make recall of an event less accurate; leading questions are one cause.
- CONTEXT Identifying the Culprit: Assessing Eyewitness Identification. National Academies Press, 2014-10-02. Review of eyewitness research with recommendations for police and courts.
Ledger updated 7 Nov 2026. Open this ledger as its own page · The P(n) Board · Method
Themes: Memory · Surveillance and scoring
