In "Trevor", Agents Mulder and Scully search for an escaped convict in Mississippi who was suspected of killing his prison warden under mysterious circumstances.

They then set out to find and apprehend him, but in doing so, Agents Mulder and Scully quickly discover that he has the uncanny ability to pass through solid, conductive materials.

"Trevor" was co-written by Ken Hawryliw and Jim Guttridge, who developed a partnership after working on the television series Millennium.

In addition, many of the special effects used in the episode were created by conventional methods in order to not exceed the budget of the show; this included the removal of a scene that would have shown Pinker moving through the walls in a motel.

In Stringer, Mississippi, inmates are being made to prepare and fortify a prison farm for a series of devastating tornadoes, which are due to pass through within the next few hours.

One of the guards later finds the warden's body split in half around the waist, propping his office door shut from the inside.

Meanwhile, in Meridian, a woman named June Gurwitch is disturbed when she watches a news report on Pinker's apparent death.

June has changed her last name to avoid Pinker; the agents find her living with her new boyfriend and convince her to go into witness protection.

Pinker, who was hiding in the trunk of the agents' car, leaves a charred message on June's house wall reading "I want what's mine", but the agents discover when this writing stops at the glass of a mirror that glass, acting as an insulator to electricity, repulses Pinker's abilities.

Scully finds medical bills indicating that June gave birth to a child and learns that Pinker is actually in search of his son, whom he has not yet met.

June is placed in a motel by the Mississippi Highway Patrol, but Pinker kidnaps her after killing the trooper assigned to guard her.

[2] Hawryliw later explained that the idea to make Pinker search out his son came from a desire to humanize the antagonist: "There's this unique man who can walk through walls.

This scene was cut not only because it proved too expensive, but also because the writers were hoping "to shift the episode's emphasis from the supernatural to the emotional.

[3] Director Rob Bowman used a combination of "clever camera angles, strategic use of breakaway cement, and—in the case of Mulder's trunk lid—the miracle of auto-body repair substance Bondo" to avoid going over-budget.

[3] Eventually, the crew was able to create a breakaway section that "suggested, rather than outlined perfectly", the shape of a human body.

[8] The two noted that the episode had only one good visual gimmick; the ability for Pinker to walk through walls, which, they argue, was never exploited to its full extent.

The review also criticizes that the episode tries "a reversal and make Pinker an object of the audience's sympathy, rather than the story's villain".

Paula Vitaris from Cinefantastique gave the episode a moderately positive review and awarded it two-and-a-half stars out of four.

[11] Vitaris, despite criticizing the shaky science behind the tornado with the ability to allow someone to pass through matter, called the episode's special effects "superb": she later cited the "fake corpses" as the best examples.