Encounter File 017: Bigfoot – The Patterson–Gimlin Film
Case Information
File No.: 017
Classification: Hominid Cryptid
Cryptid: Bigfoot
Region: Bluff Creek, Northern California
First Report Referenced: October 20, 1967
Case Status: Open – Film Authenticity Disputed
Confidence Level: ★★☆☆☆
Primary Evidence: 16 mm Film, Eyewitness Testimony, Footprint Casts
Filed By: Chasing Cryptids Field Research Department
Incident Summary
On October 20, 1967, Roger Patterson and Bob Gimlin were riding through the Bluff Creek region of Northern California when they claimed to encounter a large, hair-covered figure walking along a sandbar.
Patterson retrieved a rented 16 mm motion-picture camera and began filming as the figure moved away from them.
The resulting footage lasts less than one minute.
Its most famous moment occurs when the subject turns its upper body and looks back toward the camera before continuing toward the tree line.
The figure’s apparent size, muscular build, prominent breasts, long arms, and unusual gait led Patterson and Gimlin to identify it as a female Bigfoot.
Researchers later gave the subject the nickname Patty.
The Patterson–Gimlin Film became the most recognizable visual evidence in Bigfoot history. For nearly six decades, supporters have argued that the subject’s anatomy and movement would have been extremely difficult to reproduce with a costume in 1967.
Skeptics maintain that the film shows a person wearing a carefully constructed ape suit.
In 2026, the debate intensified when the documentary Capturing Bigfoot presented newly discovered footage alleged to show a costumed rehearsal connected to Patterson’s earlier filmmaking activities.
The new evidence has not ended the argument. It has made the film’s uncertain history even more important.
Investigation
Roger Patterson had been interested in Bigfoot for several years before the Bluff Creek encounter.
He self-published Do Abominable Snowmen of America Really Exist? in 1966 and had begun working on a Bigfoot-themed documentary or docudrama before the October 1967 expedition.
Patterson and Gimlin traveled to the Bluff Creek region after reports of large tracks in the area.
According to their account, they were riding upstream on horseback during the early afternoon when they rounded an overturned tree and saw a large figure near the creek.
The horses reacted suddenly. Patterson dismounted, retrieved his Cine-Kodak K-100 camera, and began filming while moving across the uneven ground.
The early portion of the footage is unstable. As Patterson steadied himself, the film captured a clearer view of the subject walking away.
The figure appeared to be:
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Covered in dark brown or reddish-brown hair
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Walking upright on two legs
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Broad across the shoulders and torso
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Possessing long arms
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Moving with a steady, swinging stride
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Female, based on visible breasts
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Calmly retreating rather than running
Patterson estimated the creature’s height at between six and seven feet, although later estimates varied considerably.
Gimlin remained behind with a rifle while Patterson followed the figure and continued filming. The subject eventually entered the trees and disappeared.
The men reportedly examined the path afterward and found large footprints in the creek bed.
Patterson left the area to arrange for the film to be shipped for processing. Gimlin remained near the site for part of the evening before the two men departed.
Researchers returned to Bluff Creek and created plaster casts of tracks attributed to the filmed subject.
The film was developed and publicly shown soon afterward, beginning a controversy that has continued ever since.
Evidence Reviewed
Film Evidence
The Patterson–Gimlin footage was recorded on 16 mm color film using a Cine-Kodak K-100 camera.
The creature sequence contains approximately 950 frames and lasts roughly one minute, depending on the frame rate used during playback.
Analysis is complicated by uncertainty concerning the camera’s exact recording speed. Estimates commonly range from 16 to 24 frames per second. Changing the playback speed affects how the subject’s gait appears.
The surviving copies reveal:
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An upright, hair-covered figure
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Visible breasts
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Long, swinging arms
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A rotating upper body during the backward glance
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Apparent movement beneath the hair or surface of the body
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A steady gait across uneven terrain
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No clearly visible mask line or costume opening
The original camera film is no longer available for modern forensic testing. Researchers generally work from first-generation copies, duplicate films, scans, and individual frames.
Loss of the original limits any definitive analysis of the image grain, editing, exposure, and physical film stock.
Footprint Evidence
Tracks attributed to the subject were reportedly found along the route shown in the film.
Researchers documented and cast some of the impressions.
The footprints were described as approximately fourteen to fifteen inches long, although measurements vary among sources.
Supporters point to the depth of the impressions and the apparent stride length as evidence of a large, heavy animal.
Skeptics note that artificial feet can create convincing tracks, particularly in soft creek-bed material. Questions also remain about whether every cast associated with the case came from the exact filmed trackway.
Eyewitness Testimony
Roger Patterson and Bob Gimlin consistently maintained that they encountered an unknown living creature.
Patterson promoted the footage heavily until his death from cancer in 1972.
Gimlin largely avoided the publicity surrounding the film for many years. He later began discussing the encounter publicly and continued to deny participating in a hoax.
Their presence at Bluff Creek is established. The disputed question is whether they unexpectedly filmed an unknown animal or staged the scene.
Site Evidence
Bluff Creek is a remote, forested region within Northern California’s Six Rivers National Forest.
Flooding and vegetation growth altered the site after the filming, making later measurements difficult. Researchers eventually relocated the likely film location and reconstructed portions of the subject’s path.
Site studies have been used to estimate:
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Subject height
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Distance from the camera
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Length of the visible path
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Position of trees and logs
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Camera angle
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Walking speed
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Footprint spacing
Different assumptions have produced different results. No single reconstruction has resolved the subject’s identity.
Newly Reported 1966 Footage
In March 2026, the documentary Capturing Bigfoot, directed by Marq Evans, premiered at the South by Southwest Film & TV Festival.
The documentary presented a previously unreleased reel of 16 mm film reportedly discovered in the belongings of Norm Johnson, a former Boeing film-department employee.
The footage is said to date from 1966 and reportedly shows a hair-covered figure walking through a wooded setting during what the filmmakers believe was a Bigfoot costume test or rehearsal.
The documentary argues that Johnson had connections to Patterson’s filmmaking circle and that the newly discovered material supports the conclusion that the famous 1967 encounter was staged.
The production also includes statements attributed to Roger Patterson’s son, Clint Patterson, concerning a costume reportedly used by his father.
The footage has renewed scrutiny of the case. Its date, full provenance, relationship to the Bluff Creek film, and interpretation require continued independent examination.
Even if the 1966 reel depicts a costume test, investigators must still demonstrate that the same costume, participants, and plan produced the 1967 footage.
Findings
Several explanations have been proposed for the Patterson–Gimlin Film.
Unknown Hominid
Supporters argue that the footage depicts an undocumented North American primate or surviving hominid.
They point to:
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Apparent muscle movement
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Unusual body proportions
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Long arms
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Broad shoulders
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Compliant or flexible foot movement
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A gait they believe differs from ordinary human walking
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Visible female anatomy
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Lack of an obvious costume seam or mask
Some analysts contend that creating a suit with these features would have exceeded the resources available to Patterson in 1967.
This explanation requires the existence of a breeding population of large primates for which no confirmed body, bone, fossil, or genetic evidence has been recovered.
Person Wearing a Costume
The conventional skeptical explanation is that the figure was a human performer wearing an ape suit.
Patterson’s prior Bigfoot interest and his work on a Bigfoot film project gave him knowledge of the legend and a possible reason to stage convincing footage.
A costume could explain:
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Humanlike posture
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Familiar walking mechanics
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The subject’s lack of panic
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Its controlled path across the clearing
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The convenient filming opportunity
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The absence of physical evidence beyond tracks
The main difficulty is identifying the exact costume and demonstrating how it produced the body shape visible in the film.
No original suit has been recovered.
Bob Heironimus’s Claim
Bob Heironimus, an acquaintance of Patterson and Gimlin, later claimed that he wore the costume used in the film.
He described participating in a staged event and identified features of the suit and filming process.
Supporters of the film dispute his account, citing inconsistencies, the late timing of his public claim, and the absence of the alleged costume.
Heironimus’s testimony supports the hoax theory but does not independently prove it.
Philip Morris Costume Claim
Costume maker Philip Morris stated that he sold Patterson a gorilla suit and later explained how it could have been modified.
Critics of the film consider this a possible explanation for the subject’s appearance.
However, no purchase records or surviving costume have conclusively connected a Morris suit to the Bluff Creek footage. Recreations have not achieved universal agreement as an exact visual match.
Film-Speed and Gait Effects
The subject’s unusual movement may partly result from playback at the wrong speed.
When the recording speed is unknown, movement can appear heavier, faster, slower, or less human than it actually was.
Some gait specialists have reproduced parts of the walk with a human performer. Other analysts argue that certain combinations of stride, knee flexion, arm length, and body rotation remain difficult to duplicate.
Gait analysis has produced interesting observations but no consensus.
Deliberate Hoax Involving a Skilled Costume
A carefully planned hoax could account for the film, tracks, remote location, and rapid publicity.
The figure would not have required Hollywood-level detail because it was filmed from a distance with a handheld camera on grainy 16 mm stock.
The 2026 rehearsal footage, if authenticated and conclusively connected to Patterson’s production, could provide the strongest evidence yet for this explanation.
At present, it strengthens the hoax hypothesis without independently resolving every question surrounding the 1967 reel.
Current Assessment
The Patterson–Gimlin Film remains the most significant visual artifact associated with Bigfoot.
Unlike a distant light, single photograph, or brief modern video, the film provides hundreds of frames showing a complete figure in motion. That makes it unusually valuable for comparison and analysis.
It also provides more opportunities for conflicting interpretation.
Supporters see anatomical detail, natural movement, and a creature too sophisticated for a 1967 costume. Skeptics see a human gait, suspicious circumstances, and a filmmaker who was already attempting to produce Bigfoot-related material.
The missing original film and missing costume prevent direct forensic resolution.
The 2026 Capturing Bigfoot evidence meaningfully changes the case. A verified rehearsal involving Patterson’s associates and a costumed Bigfoot would make accidental discovery at Bluff Creek considerably less likely.
However, the new footage must be evaluated on its own provenance and physical evidence. A documentary’s conclusion is not a substitute for independent verification.
The Patterson–Gimlin Film has not been universally proven authentic or conclusively connected to a recovered costume. Its authenticity remains disputed, although the cumulative evidence increasingly supports serious consideration of a staged production.
Investigator’s Notes
Frame 352, showing the subject turning toward the camera, became the defining image of Bigfoot.
That single frame has influenced nearly every later depiction of the creature, from documentaries and witness illustrations to roadside statues and popular culture.
This creates an investigative problem.
Later witnesses may describe what they actually observed, but their expectations of what Bigfoot should look like have already been shaped by the Patterson–Gimlin figure.
The film is therefore more than evidence within the legend. It helped build the modern legend itself.
The case also demonstrates why preserving original evidence matters. If the original film, camera settings, complete development records, track documentation, and all related footage had remained together, modern forensic analysis might answer questions that copies and recollections cannot.
Future Encounter Files may examine:
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The Bluff Creek trackway
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Bob Heironimus’s hoax claim
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The 2026 Capturing Bigfoot evidence
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Roger Patterson’s earlier Bigfoot film project
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Anatomical and gait studies of Frame 352
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The 1958 Bluff Creek footprints
References
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Roger Patterson and Bob Gimlin, Patterson–Gimlin Film, October 20, 1967
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Skeptical Inquirer, “Documentary’s Devastating Bigfoot Debunking”
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John Napier, Bigfoot: The Sasquatch and Yeti in Myth and Reality
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David J. Daegling, Bigfoot Exposed: An Anthropologist Examines America’s Enduring Legend
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Grover Krantz, Big Footprints: A Scientific Inquiry into the Reality of Sasquatch
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Greg Long, The Making of Bigfoot: The Inside Story
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Bill Munns, When Roger Met Patty
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Historical interviews with Roger Patterson and Bob Gimlin
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Bluff Creek site surveys and footprint documentation
Chasing Cryptids Assessment
The Patterson–Gimlin Film is extraordinary evidence of something, but identifying that something remains the problem.
It may preserve a brief encounter with an undocumented hominid. It may instead be an exceptionally effective piece of staged filmmaking whose limitations helped make it convincing.
The film has survived because neither side has produced the one piece of evidence that would end the debate: a confirmed Bigfoot specimen or the original costume conclusively matched to the figure.
The newly revealed 1966 footage gives the hoax explanation additional weight and deserves careful independent study. Until that connection is fully established, the case should remain open rather than declared solved.
Whatever ultimately crossed the Bluff Creek sandbar, the Patterson–Gimlin Film permanently changed how the world imagines Bigfoot.