On February 28, 2199, a routine infrastructure survey of Underworld Sector 7, levels B34 through B38, detected electromagnetic field anomalies exceeding baseline measurements by a factor of 2,700. The survey team, consisting of four certified deep-level technicians equipped with standard-issue Faraday-shielded instruments, reported that their equipment began producing readings that should have been physically impossible — negative resistance values, current flowing in directions that contradicted the wiring topology, and temperature sensors registering heat signatures in sealed, unpowered chambers.

The investigation team deployed on March 3 found no conventional source for the anomalies. No active power conduits exist below B32 in Sector 7 — the infrastructure was decommissioned in 2161 and has been dark for nearly four decades. Yet the EM readings persisted, strongest near a cluster of collapsed maintenance tunnels that the team was unable to access due to structural instability. Thermal imaging through the debris showed intermittent heat blooms in a rhythmic pattern — approximately 72 cycles per minute — that one team member described as "like a heartbeat" before being reminded to keep subjective interpretation out of the official record.

Soil and air samples collected at the anomaly site contained elevated levels of an unidentified bioluminescent compound, similar to but distinct from known luciferin analogs. The compound degraded within six hours of collection, making laboratory analysis incomplete. What data was obtained suggests a protein structure that does not match any cataloged organism — terrestrial, synthetic, or engineered.

The investigation was suspended on March 9 when a section of ceiling collapsed near the primary anomaly site, injuring one team member. The official conclusion is "electromagnetic interference from degraded infrastructure interacting with residual industrial chemicals," a classification that satisfies administrative requirements without explaining the rhythmic thermal patterns, the impossible instrument readings, or the bioluminescent compound that shouldn't exist. A follow-up investigation has been recommended but not funded.