"Infection" is the fourth episode of the first season of the television show Babylon 5. To explain the events of "Infection", a few comments on the history of science fiction in television must be made.
Before Babylon 5, there had been only one show that had succeeded widely in the science-fiction genre: Star Trek. Although Gene Roddenberry's original vision for Star Trek was in many ways conceptual, those who remember watching either The Original Series or (The Next Generation) probably remember the portion of each episode where Captain Kirk would either throw punches or seduce an alien woman. This makes JMS' attempts to market a show where people sit around a conference table and have involved diplomatic discussions even a harder sell. Which is why, in some of the earlier episodes of Babylon 5, the concept doesn't seem to gel totally.
And thus we get to the point of "Infection"-- it is in many ways a Star Trek episode in Babylon 5 colors. The plot revolves around a mysterious alien artifact, made of a combination of organic technology and unobtanium, which transforms a man into a shambling, murderous robot-looking-thing, whose special effects were probably pretty impressive in 1994, but look fairly dated now. When Jeffery Sinclair confronts the creature, he makes a speech reminiscent of Captain Kirk, even using William Shatner's cadences as he makes a high flown speech about humane behavior, in between trading punches. I was left underwhelmed.
If this episode has a saving grace, it is the conversation between security chief Garibaldi and Sinclair afterwards, where Garibaldi asks Sinclair why exactly he feels the need to play the hero, which somewhat deconstructs what would otherwise be a thin piece of alien-invasion space opera.