A lone government contractor is exploring a Cold War-era nuclear research laboratory, either to determine if it can be safely destroyed or as a fact-finding foray into previously-unknown governmental collusion.
He notes that there are many barrels of unlabeled materials, many of which are leaking, and bodies clad in old hazmat suits strewn about the complex.
As he explores he realizes he is not alone, and that two different hazmat suits are chasing him, encouraging him to open fire. Some of his shots ignite/explode nearby barrels and several large explosions rock the underground base. As his vision clears he realizes that the two suits have only chased him independently, and never seemed to work together to corner him.
Out of bullets and with one suit approaching, he grabs a piece of rebar and moves to stab the creature, screaming “I’m going to kill you!” It lets him, opening its arms wide in a welcoming gesture. He slows, realizing that it wants to die; that it had been provoking him solely with the intention for him to end its existence. He details the wounds he inflicted on it, and notes far older damage.
At that point he either realizes or remembers that Russian and Brazilian nuclear scientists were working on new kinds of warheads and munitions but the sides had a falling out after a criticality accident that was largely hidden from the media.
These two scientists were in the test lab during the accident and while all of their companions died, they were unable to, and have spent the past 40 years hating each other, blaming the other for what happened.
Seeing a new face, an armed one at that, and being largely unable to speak, they both arrived at the conclusion that this interloper could be prodded into killing them, ending their long torment.
With the explosions having sealed the entrance to the laboratory, he wonders if he will share the same fate as these two, or fall and die like their companions.