Several months after the events of The Fly, Veronica Quaife delivers Seth Brundle's child. After giving birth to a squirming larval sac, she dies from shock. The sac then splits open to reveal a seemingly normal baby boy. The child, named Martin Brundle, is raised by Anton Bartok, who is the owner of the company which financed Brundle's teleportation experiments and fully aware of the accident which genetically merged Seth Brundle with a housefly. Martin grows up in a clinical environment. His physical and mental maturity is highly accelerated, and he possesses a genius-level intellect, incredible reflexes, and no need for sleep. He knows he is aging faster than a normal human, but is unaware of the true cause, having been told his father died from the same rapid aging disease.
At age 3, Martin has the physique of a 10-year-old, and frequently sneaks around and explores the Bartok complex. He finds a room containing laboratory animals, and befriends a dog. The next night, he brings it some of his dinner, only to find it missing. He enters an observation booth overlooking Bay 17. There, scientists have managed to reassemble Brundle's Telepods, but not to duplicate the programming that enabled them to teleport living subjects. An attempt to teleport the dog fails, leaving it horribly deformed. It maims one of the scientists, horrifying young Martin. Two years later, Martin's body has matured to that of a 25-year-old. On his fifth birthday, Bartok presents Martin with a bungalow on the Bartok facility's property. He also offers Martin a job: repair his father's Telepods. He apologizes about the dog and assures Martin that its suffering was brief. When Martin is uneasy about the proposition, Bartok shows him Veronica Quaife's videotapes, which documented Seth Brundle's progress with the Telepods. Seeing his late father describe how the Telepods ostensibly improved and energized his body, Martin accepts Bartok's proposal.
As he begins work on the Telepods, Martin befriends an employee, Beth Logan. Beth invites Martin to a party at the specimens division, where learns that the mutated dog is still kept alive and studied. Thinking Beth is aware of the dog's imprisonment, Martin argues with her, leaves the party, and goes to the animal's holding pen. The deformed dog, in terrible pain, still remembers Martin, who tearfully euthanizes it with chloroform. Martin reconciles with Beth, and rearrives at his father's "eureka" moment when he realizes the Telepod's computer need to be creative to analyze living flesh. Martin then shows Beth his perfected Telepods by teleporting a kitten without harm. They become lovers, but Martin begins showing signs of his eventual mutation into a human-fly hybrid. Martin devises a potential cure for his condition, which involves swapping out his mutated genes for healthy human genes. Martin shelves this idea when he realizes the other person would be subject to a grotesque genetic disfigurement.
Eventually, Martin learns that Bartok has hidden cameras in his bungalow. Martin breaks into Bartok's records room, where he learns of his father's true fate. Bartok confronts Martin and explains that he's been waiting for his inevitable mutation. He reveals his plan to use Martin's body and the Telepods' potential for genetic manipulation for profit. Martin's insect genes fully awaken and his transformation into a human-insect hybrid begins. He escapes from Bartok Industries. Bartok is unable to use the Telepods, as they are locked by a password. Martin also installed a computer virus which will erase the Telepods' programming if the wrong password is entered. Bartok orders a search for Martin.
Martin goes to Beth and explains the situation. The two flee. They visit Veronica Quaife's old confidant, Stathis Borans, who confirms for Martin that the Telepods are his only chance for a cure. They keep running, but Martin's physical and emotional changes become too much for Beth to handle, and she eventually surrenders them both to Bartok. Without revealing the password, he becomes enveloped in a cocoon. Bartok interrogates Beth for the password. Shortly after, the fully transformed "Martinfly" emerges from his cocoon and breaks into Bay 17. He grabs Bartok and forces him to type in the password. He then drags Bartok and himself into a Telepod. Martinfly gestures Beth to activate the gene-swapping sequence and, despite Bartok's protests, Beth complies. Martin is restored to a fully human form, while Bartok is transformed into a freakish monster.Eric Stoltz as Martin Brundle
Sterling Cottingham as baby Martin (newborn)
Rodney Clough Jr. as Martin Brundle (1½ years old)
Matthew Moore as 4-year old Martin
Harley Cross as Martin Brundle (age 10)
Daphne Zuniga as Beth Logan
Lee Richardson as Anton Bartok
John Getz as Stathis Borans
Frank C. Turner as Dr. Shepard (credited as Frank Turner)
Ann Marie Lee as Dr. Jainway
Garry Chalk as Scorby (credited as Gary Chalk)
Jerry Wasserman as Simms
Saffron Henderson as Veronica Quaife
Jeff Goldblum (uncredited archive footage) as Seth Brundle
As with the first film, special makeup and creature effects were provided by Chris Walas, Inc. As opposed to Seth Brundle's diseased deterioration into "Brundlefly", in The Fly II, Martin's metamorphosis is much more of a natural evolution (as a result of the fact that Martin was already born with human-insect hybrid genes instead of being accidentally fused with a fly the way his father was).
Here is a breakdown of Martin Brundle's transformation into the creature dubbed "Martinfly" by the CWI crew (behind-the-scenes information is in italics).STAGE 1 (on view in the scenes where Martin confronts Dr. Shepard and then attempts to telephone Beth Logan): Martin's face is slightly discolored, and he's looking haggard. Worse, a bizarre cavity in his left arm has appeared, and sticky, web-like threads are being excreted from it. Eric Stoltz's face was subtly discolored with makeup, and a gelatin makeup appliance was affixed to his left arm. The webbing coming out of Martin's arm was made from Halloween-style decorative spider-webbing.
STAGE 1-A (on view when Martin views the various Bartok surveillance tapes, and when he subsequently escapes from the Bartok complex): Martin is looking even more haggard, and the skin beneath his eyes is puffy. This is an accentuated version of the Stage 1 makeup, with gelatin eyebags added under Stoltz's eyes.
STAGE 2 (on view when Martin talks to Beth inside her houseboat, as well as in the deleted "Stopping for Food" scene which can be seen on the 2005 The Fly II: Collector's Edition DVD): Martin's bone structure has started to shift, and his face is rapidly becoming deformed. Gelatin appliances were added to Stoltz's face to give the impression that Martin's brow and cheekbones were becoming distorted.
STAGE 3 (on view when Martin and Beth visit Stathis Borans, as well as when they arrive at the motel): Martin's entire head is deformed, his hairline is receding, and his voice is deepening. Also, the stringy white webbing is being excreted from his face now. Gelatin makeup appliances were added to Stoltz's entire head, and his voice was artificially lowered in post-production.
STAGE 4 (on view inside the motel, and when Bartok arrives to retrieve Martin): Martin (his voice now even deeper) has begun to instinctively pull the webbing out of his own body and wrap it around himself. As it hardens, the webbing begins to form a cocoon. At this point, Martin's legs have been enveloped by said cocoon. Now that Martin is no longer wearing clothes, a hideous assortment of lumps and bumps can be seen on his discolored body, his face and head are even more distorted, and his teeth and ears are receding. Some of his fingers are webbed together with flaps of skin, and claws are growing on his knuckles. Martin removes his human right eye in this stage to reveal an orange insect eye behind it. The most complex makeup, this stage took some 12 hours to apply to Eric Stoltz, and he was required to remain immobile on the motel couch (with his legs inside the partial cocoon) all that time, as well as during the additional hours of filming that immediately followed. Body makeup and gelatin bumps were added to Stoltz's arms and torso, in addition to the makeup appliances covering his face and head.
Soon, Martin is fully enveloped by the cocoon (which begins as slightly transparent, with the next stage becoming opaque and iridescent). The scene featuring Bartok talking to the cocooned Martin involved a Martin rod puppet—transformed from the waist-down—being operated inside a transparent composite cocoon that was filled with water.
After a brief gestation period, the final "Martinfly" creature is revealed when it bursts out of the cocoon and goes on a rampage around the Bartok complex. The iridescent creature has four arms (the top pair featuring two large, clawed digits, and the other pair having four webbed digits), two digitigrade legs, and its green body is covered with insect hairs. Martinfly is also tall and slender, with a segmented torso. Its head has piercing, orange insect eyes (with pupils), distorted nostrils, and two flexible mandibles with sharp teeth covering a mouth full of even more teeth. The interior of the creature's mouth contains a pseudo-proboscis, which can spray corrosive enzymes at high velocity. Whereas the Brundlefly creature in the first film was deformed and sickly-looking, Martinfly possesses better symmetry and is very strong, very fast, and very deadly. The final Martinfly creature was created as a series of cable-controlled and rod-operated puppets.
The Fly II grossed $20,021,322 at the US box office and a further $18,881,857 abroad, resulting in worldwide total of $38,903,179. Despite this, the film received negative reviews from critics. Many believe that Walas (who was the special effects engineer for the Oscar-winning make-up and creature effects in the first film) set out to repeat the success of the original by relying more on heavy gore and violence than on plot and atmosphere. However, it is appreciated by many fans of the horror genre for its great visual impact. Walas has stated that the film was designed to be much more of a traditional (albeit gory) monster movie than Cronenberg's horror/tragic love film.
The scene of a character's head being crushed by an elevator aroused some controversy with the MPAA: they originally gave the film an "X" rating due to its graphic nature. Ultimately, Chris Walas was able to gain a more audience friendly "R" rating after reediting the sequence. The VHS and DVD versions retain the full scene.
The film received a certain amount of backlash regarding the 'mutant' dog, in particular, the scene where Martin mercifully euthanizes the dog, which is hideously deformed and kept in a large observation room. Many viewers were disturbed by the dog's appearance and sad fate as mentioned by Chris Walas in the documentary for the Special Edition DVD. He said the audience would feel more sympathy for a mutated animal than a human.
The Fly II holds a 27% approval rating on Rotten Tomatoes from a sample of 15 critics.
Beginning in March 2015, IDW Publishing released a five-issue comic book miniseries titled The Fly: Outbreak, written by Brandon Seifert. The story is a direct sequel to the events of The Fly II, and features Martin Brundle inadvertently causing a transgenic outbreak while attempting to cure Anton Bartok, to whom he had previously transferred his mutant genes.