Shadowzone

Captain Hickock arrives at Jackass Flats Proving Ground, a subterranean facility from 1962 now housing Project Shadowzone. He has been sent to investigate the death of a Shadowzone test subject. Tommy Shivers escorts him through the largely abandoned complex as they meet Dr. Erhardt, Dr. Kidwell, and Dr. Van Fleet.

The team explains that the experiment induces extended deep sleep (EDS) in the two remaining patients. To prove it isn’t life-threatening, Hickock insists the test be repeated with a longer duration under the same parameters. The sleep chambers and computer systems sit at the heart of the operation.

During the extended sleep test, the male subject’s veins swell and his head explodes. Alarms blare as the main power transformer blows, triggering an emergency shutdown and sealing the lab. The facility falls into darkness as the crisis unfolds.

With power down, the team moves the female subject’s sleep chamber into the computer lab to monitor the second patient. Wiley detects a fifth life form on the heat-signature screen and notes the presence of John Doe as he arrives. Tension rises as the unexpected entity shows up in the facility.

Dr. Jonathan Van Fleet seals himself in the lab and is attacked and killed by John Doe. The others react with shock, and Erhardt begins to articulate the implications of their encounter with the new form. The threat feels all too real as they regroup.

Erhardt explains that their sleep experiment uncovered a gateway through the unconscious mind to a parallel dimension. She theorizes that John Doe entered their world through the remaining male test subject, linking the death to a bigger mechanism. The team debates the risks of continuing the experiments.

Wiley finds that John Doe is no longer on the heat signature and theorizes the creature can expand and contract its molecular structure. It seems to have escaped through a drain pipe, and the lab’s emergency airlock is triggered, sealing everyone underground. The team braces for the creature’s next move.

Cutter hears a screeching from a lab monkey and investigates the wall; a massive deformed rat bursts out and tears off her arm. Kidwell discovers the monkey and radios Shivers for help, but the situation rapidly escalates as the animal threat spreads. The facility’s safety is failing and panic grows.

Shivers discovers Cutter’s body and panics, firing his shotgun as the group pursues the source of the noises. Wiley and Hickock abandon their attempt to repair the transformer and follow the sounds, only to find gore splattered on the walls and ceiling. The danger shifts from the creatures to the collapsing environment.

Wiley manually restores power to the elevator, but the system shorts out and only Hickock can reach the lab level. Wiley’s blood splatters against the elevator window as he is pulled offscreen, sealing his fate. Hickock climbs through the top of the elevator to reach the lab.

Back in the computer lab, Erhardt becomes fascinated by the entity and theorizes it can shapeshift and form based on human thought. She notes that John Doe could even assume the form of Van Fleet’s phobia before killing him. The creature’s adaptability becomes clearer but more terrifying.

Power returns and the creature reappears in the test lab, taking control of the computer system and communicating that it is dying and needs to return to its own dimension. It promises to spare them if they help it go back, injecting a glimmer of reluctant mercy into a deadly encounter.

Hickock connects the female subject for another EDS to open a portal to the other dimension. Erhardt insists on witnessing and inserts a metal rod into the portal, watching it pulled through. She briefly steps inside, then reemerges excitedly, declaring, 'There are thousands of them,' before the rod is thrust back and impales her chest.

The creature emerges, examines Jenna’s pod, roars at Hickock, and drags Erhardt’s body back into the portal. The team realizes the gateway remains a threat even as it recedes. The lab falls quiet save for the looming possibility of more visitors from the other side.

Hickock destroys the computers with a fire axe, and an electric shock knocks him unconscious. He wakes to find Jenna revived and released from the sleep chamber as the credits roll. The immediate danger has passed, but the mystery of the portal lingers.