It was written by series creator Chris Carter and staff writer Howard Gordon, and directed by Rob Bowman.

The show centers on FBI special agents Fox Mulder (David Duchovny) and Dana Scully (Gillian Anderson) who work on cases linked to the paranormal, called X-Files.

"F. Emasculata" was based on the actual practice of pharmaceutical companies sending scientists all over the world looking for plants and animals that could have medicinal use.

The X-Files director Frank Spotnitz felt that the episode's exploding pustules were ridiculous because of their over-the-top nature.

In the Costa Rican rainforest, entomologist Robert Torrance discovers a decomposing boar carcass covered with purple pustules.

Simultaneously, in Dinwiddie County, Virginia, a prison inmate also named Robert Torrance receives a package containing an infected leg of meat.

Scully traces Torrance's package to Pinck Pharmaceuticals, a major drug developer, and finds an insect in another prisoner's body.

Dr. Osbourne, now visibly infected, reveals that his team works for Pinck and is researching a dilating enzyme produced by the insect.

[2] Initially, the show's producers were worried about releasing the episode around the same time as the film Outbreak—a movie in which a deadly, contagious disease spreads in a California town.

"[3] The X-Files director Frank Spotnitz remarked, "When we saw the pustule bursting on film, we just laughed because it was just so over-the-top grotesque.

"[4] The Lower Seymour Conservation Reserve, North Vancouver stood in for the Costa Rican jungle; this location had previously been used for the season opener "Little Green Men".

Entertainment Weekly graded the episode a C, writing, "A good idea is tainted by plot holes as gaping and disturbing as the pustular boils you'll be treated to in this hour".

[10] Robert Shearman, in his book Wanting to Believe: A Critical Guide to The X-Files, Millennium & The Lone Gunmen, rated the episode three-and-a-half stars out of five.

[11] He was, however, more critical of the second half, noting that the story "takes a left turn and becomes a thoughtful analysis on disinformation, on cover-up, and the public right to truth.