Frank investigates an allegedly mythical Russian serial killer with an informer who he suspects is holding back information.
In New York City, a man named Yaponchik (Levani Outchaneichvili) shoots a man in the face, preventing the victim's identification; this is the third such murder committed this way. Millennium Group consultant Frank Black (Lance Henriksen) is asked to aid the New York Police Department investigate the case. Black is joined by a Muscovite investigator, Yura Surova (Boris Krutonog), and an undercover agent, Andrei Medikov (Dmitri Boudrine). Examining the victim's body, a symbol is found on the corpse resembling an inverted V, but its meaning is unknown.
Black, Medikov and Surova visit a Russian nightclub where the latter two are working undercover. As Surova and Black talk at one table, Medikov is approached by Yaponchik. Someone in the club recognizes Yaponchik, and the crowd stampede out of the building when they hear his name. After the crowd has dispersed, Black and Surova find Medikov's body at a table, his face shot off.
Surova explains to Black that Yaponchik has come to be regarded by Russians as a sort of evil folkloric figure. Meanwhile, Group member Peter Watts (Terry O'Quinn) determines that the "V"-like symbol found earlier is actually a fragment of the Chi Rho, a Christian symbol. Watts also informs Black that many Russians believe Yaponchik to have directly responsible for the Chernobyl disaster, a Soviet nuclear meltdown tied by some to Biblical prophecies of the apocalypse. Black researches the disaster, finding a picture of both Medikov and Surova at the Chernobyl nuclear plant, and realizes that both men have been tracking Yaponchik for revenge.
One of Yaponchik's victims is identified as a restorer of Russian icons. Her home is searched, and it is found that she had uncovered Yaponchik's identity and attempted to appease him by sending him several icons. Black feels Yaponchik is killing in order to perpetuate the legends surrounding him by instilling fear in those who believe them. Watts and Black visit the Russian Embassy to find the man the icons were being mailed to—Sergei Stepanovich, identifiable as Yaponchik. Stepanovich is protected by diplomatic immunity; however, it becomes clear that Surova, Medikov and an Orthodox priest who aided the investigation have all been stalking Stepanovich, who they believe to be the Antichrist.
Yaponchik murders another two men at a bathhouse, but is confronted by Surova. Yaponchik tells Surova he cannot be killed. Surova ignores this, and shoots him in the head. Yaponchik is then found and rushed to hospital. Black sees the crime scene at the bathhouse, and draws a connection between Yaponchik and the beast from the sea in the Biblical Book of Revelation, who is said to survive a fatal head wound; fearing that Yaponchik will likewise survive, Black heads to the hospital. Surova beats him there, however, and confronts the recovered Yaponchik. As Surova is about to shoot his quarry again, he is convinced instead that Yaponchik is "not the one" he is thought to be. Surova helps Yaponchik make his way to the helipad on the hospital's roof. Black and Watts arrive on the roof in time to see Yaponchik escorted onto a helicopter by several men, who take off before they can be apprehended.
- Levani Outchaneichvili (Yaponchik) previously played John Mostow in The X-Files episode "Grotesque".
- Dmitri Boudrine (Andrei Pietrovich Melnikov) previously played Russian Engineer in The X-Files episode "The Host".
- Bill Croft (Broadface) previously played Căluşari #2 in The X-Files episode "The Căluşari" and Comrade Svo in "Never Again".
- Roger Haskett (E.R. Doctor) previously played Deputy Dennis Tyson in The X-Files episode "Miracle Man".
- Bill Croft as Broadface
- Brian Downey as Medical Examiner
- Roger Haskett as E.R. Doctor
- Beverly Pales as Torch Singer
SEMICOLON-SEPARATED LIST OF ITEMS/LOCATIONS REFERENCED IN EPISODE (BUT NOT LINKED TO IF ALREADY LINKED IN SUMMARY OR GUEST STARS SECTIONS)