Shaggy's distant cousin Tawny invites the Mystery Gang to her ranch in Sorghum City, a town lately plagued by vandalism and rumors that the ghost of Dapper Jack Rogers—the legendary horseman and outlaw in their family tree—might be at work again. When the group arrives, the locals panic and flee at the sight of the visitors, believing Shaggy is the very ghost they fear. Tawny and her neighbor Rafe share a portrait of Dapper Jack, and they recount how the sheriff once chased the man across the desert before reports of his death faded into a haunting legend. The tale draws curious travelers, but now that ghostly attacks resume, Sorghum City seems eager to forget the truth and cling to the myth.
The gang settles into Tawny’s ranch and meets a cast of guests who will become part of the mystery. Among them is the famous preteen musician Buddy G. who carries a crippling fear of horses, a detail that complicates every plan around the surrounding stables. There are also the business pressures bearing down on Tawny, as the Black Rattler Land Company quietly buys up foreclosed properties, threatening the ranch’s future. If the ghost is meant to scare people away to preserve a real estate windfall, the gang is determined to cut through the deception and protect Tawny’s home. Dapper Jack makes another appearance that night, blasting green flames from a gun and slipping back into the shadows. Fred discovers boric acid behind the eerie glow, a clue that points away from supernatural forces and toward a calculated scheme.
As the Mystery Gang investigates, some guests are put to work under the watchful eye of ranch hands Larry and Kyle, who begin teaching ropework and riding to help everyone feel more at ease. Buddy, however, remains terrified of the horses, and even the adults stumble with the new skills. Velma Velma has a horse dander allergy that slows her down, so she and Daphne step away to explore a local museum for clues. There, they sense someone has tampered with a storeroom diary that could belong to Sheriff Carmichael, a lead that suggests more human hands behind the legend than fans and folklore.
The drama intensifies when Dapper Jack returns to the barn and starts a fire, corralling a dangerous horse named Buckstitch. Scooby-Doo has a surprising moment of calm, soothing Buckstitch with a voice that seems to understand the animal’s needs. After a few false trails and tense encounters, the gang decides to examine Jack’s grave, only to confront a furious ghost that seems determined to keep the past alive. The group escapes by borrowing a canoe from a closed rental agency and plunges downstream, narrowly avoiding a catastrophic drop over a waterfall; Shaggy’s improvised roping instincts save them all when a sudden crisis hits.
With nothing else to go on, Shaggy volunteers to enter the rodeo to win the prize money that would save Tawny’s mortgage. Scooby secretly speaks to the broncos to help Shaggy win, but a missed moment means that Shaggy must rely on his own newfound rope skills to tame a wild horse and succeed in the competition. Buddy opens the rodeo with a short concert, and this moment becomes a turning point for him as well, as Scooby helps Buddy push past his fear. The post-rodeo party reveals a new danger: a cattle stampede driven by the ghostly disturbance, forcing the Mystery Gang to act quickly to protect Buddy’s family and neighbors.
A crucial breakthrough comes when Velma notices a distinctive font on a Black Rattler business card that matches the design on Tawny’s website, linking the scheme directly to Rafe. The team uncovers Carmichael’s diary hidden by Rafe, and Velma exposes Rafe as a secret Black Rattler executive who engineered the ghostly disturbances to drive up profits and seize control of Sorghum City. The confrontation escalates as Rafe attempts to flee in a stagecoach, swapping horses to outrun the group. Scooby and Buddy manage to derail the plan: they hop aboard and free two of Rafe’s horses, sending the coach crashing. Shaggy rides Buckstitch once more, and a concussion ends with Rafe mistaking him for Dapper Jack, leading to a reluctant apology. Rafe is arrested, and the Mystery Machine backs away from the scene as Tawny vows to reveal the truth about Dapper Jack to the town.
In the quiet aftermath, Tawny thanks the Mystery Gang for exposing the real story, and the group prepares to drive away. Yet the closing scene hints at the enduring spirit of the legend: the real Dapper Jack watches from a ledge, tips his hat, and disappears, leaving a lingering sense that some histories are meant to be remembered—and some legends are best told with honesty rather than fear.
- The Mystery Gang keeps Sorghum City safe, and the truth about Dapper Jack finds its place in the town’s memory.
- The team’s bond remains strong as they roll back into the distance in the iconic Mystery Machine, ready for the next mystery on the horizon.
