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This week’s murder mystery · Thriller

Four
Kelvin.

At 02:14 on a Tuesday, Dr. Arjun Rao, Meridian Quantum's lead experimental physicist, was found dead inside the Annex's B4 cryostat vault, asphyxiated by a helium purge triggered from the control gallery. Three hours earlier he had emailed the board announcing he was retracting the ORACLE-9 paper because its headline error-correction results had been fabricated — and that one of four executives knew. The attachment proving it was quarantined seventy seconds after it sent. The vault's double-key interlock means the purge was deliberate: someone turned a key while Rao was sealed inside, forty-one hours before the Lisbon keynote that would have made the company worth eleven billion. There are four suspects. Walk to find the clues, and name the killer by night 7.

Case file · This weekSpoiler-free

4

Persons of interest

VictimDr. Arjun Rao, lead experimental physicist, meridian quantum
Age39
SettingPresent day, Zurich's Oerlikon tech corridor. The Meridian Quantum Annex is a forty-four-storey glass spike bolted onto four subterranean levels of shielded cryogenic labs — a building that gets colder the deeper you go. Outside: autobahn hum, Swiss rain, defence-ministry delegations arriving in unmarked cars. Inside: a company seventy-two hours from a Lisbon keynote that will either float it at eleven billion or expose it as the largest scientific fraud in European history. Everyone is awake. Nobody is honest.
The caseForty-one hours before the keynote, the man who could stop it froze to death behind a door only four people could lock.
Nights7, Monday to Sunday
KillerWalk to find out.

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Persons of interest

Meet the suspects.

Four suspects. Read their files and question them out loud as the week goes on. One of them did it.

Suspect 01

Helena Voss

Chief Scientific Officer, Meridian Quantum

AlibiRedacted

Suspect 02

Petra Lindqvist

Head of Legal, Meridian Quantum

AlibiRedacted

Suspect 03

Daniel Okonkwo

Head of Hardware Logistics, Meridian Quantum

AlibiRedacted

Suspect 04

Marit Solberg

Chief Information Officer, Meridian Quantum

AlibiRedacted

The week

Seven nights to solve it.

About two clues appear each night, around fifteen in all. Miss a night and they wait for you. On night seven, accusations open.

  1. MonNight 1

    The case opens.

    Read the case file. Start walking.

    Tonight
  2. TueNight 2

    First clues.

    About two clues appear.

    Tonight
  3. WedNight 3

    Meet the suspects.

    Read the files. About two clues.

    Tonight
  4. ThuNight 4

    Question suspects.

    Interrogations by voice. About two clues.

    Tonight
  5. FriNight 5

    Gather evidence.

    About two clues appear.

    Tonight
  6. SatNight 6

    Final clues.

    The last clues appear.

    Tonight
  7. SunNight 7

    Name the killer.

    Accusations open. Case closed, or wrong suspect.

    Tonight

Where it happens

The clues are on your streets.

Clues appear on a real map of your city. Shown here: San Francisco, around Ellis, Stockton and Market.

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