🔒A Hudson business built a reputation as a designer of whimsical promotional vehicles. Then, a Dark Horse appeared.

A self-described dyslexic artist, James Riseborough spent two decades building his business from a two-person operation in a Bolton barn into one of the most prominent providers of custom promotional vehicles in the country.

Expanding to a 38,000-square-foot facility in Hudson, his firm Turtle Transit built a client roster that read like a who's who of American brands, with its builds including the L.L. Bean Bootmobile and the Planters NUTmobile. Over the years, Turtle Transit has done work building experiential marketing attractions and custom vehicles for clients like the Boston Red Sox, Dunkin', Dell, NASCAR, Red Bull, Kraft Foods, and Formula 1.

The COVID-19 pandemic took a bite out of business, but Riseborough estimates the firm was worth $3 million to $6 million in 2021, when things started to go astray.

Major jobs started going horribly wrong, Riseborough said. Longtime clients stopped returning his calls. Work slowly dried up. Employees began heading for the exits, including shop manager and lead fabricator Raymond Mahon; lead salesperson and project manager Daniel Caron; and Caron's wife, Jennifer Lopez, who led the graphics department.

By 2023, bookkeeper and office manager Kimberly Troest had drifted away, moving to Florida before leaving the company altogether. Riseborough, already scrambling to keep the company afloat with his own savings, said none of the passwords she’d left granted access to the financials.

Increasingly suspicious, he hired a forensic accountant to examine the books. Riseborough said he soon discovered the company he'd spent more than 20 years building had been hollowed out from within.

“Between the building, my savings, and what I could have reasonably got for the company, I could have retired,” Riseborough said.

Instead, he said he was forced to move forward with a fire sale of the building, selling the company’s assets to what had been a rival firm.

Today, Caron, Mahon and Troest are facing criminal charges stemming from their time at Turtle Transit and while forming Dark Horse Experiential, a Lancaster-based firm Riseborough alleges was formed to use Turtle's confidential client information, designs, and resources to poach clients and divert business.

The three, plus Lopez, are also facing a civil lawsuit from Riseborough.

Attorneys representing Caron, Mahon, Troest and Lopez declined comment. The Middlesex District Attorney's Office did not respond to a request for comment.

Warning signs

Riseborough founded the firm in 2001 after building cars in his youth and attending Boston University College of Fine Arts as a sculptor.

His big break came in the late 1990s, when he connected with a company called Jackrabbit Design and landed a job converting five Land Rovers into devil-horned, green-skinned vehicles for Monster.com.

“Those monsters were all over the country,” he said. “It was a godsend.”

The project put his work in front of agencies nationally, and he left Jackrabbit to build vehicles on his own.

Riseborough's reputation grew further after a chance encounter with the Bootmobile at the Head of the Charles Regatta, where he asked handlers if he could test the doors, which Riseborough says is the hardest part of building a custom vehicle.

One handler, noting his familiarity with the process, asked if he’d done this kind of work before. A week later, the Bootmobile was in his shop for a rebuild, the start of a relationship that produced two more boot vehicles.

By 2010, Riseborough had hired Caron, Mahon, Lopez, and Troest. The four would go on to hold some of the company’s most senior roles.

In 2016, he purchased the building Turtle Transit had been using as its headquarters for $1.45 million, according to Town of Hudson property records. The company had around 25 employees by that point.

Beyond the boot, builds completed by Turtle Transit included an Oscar Mayer food truck inspired by the company's Wienermobile, a double-decker bus for soccer club Sporting Kansas City, and a virtual reality dugout for the Red Sox.

By 2021, Turtle Transit appeared to be rebounding from the pandemic. Riseborough said the company was in a position to do as much as $6 million in business that year.

That fall, Los Angeles marketing agency Havas Street expressed interest in acquiring the company. Riseborough, Caron, and Troest drove to New York City to meet with Havas Street's leadership, where Caron told the prospective buyer he was considering starting his own company, a disclosure that shocked Riseborough.

Havas Street backed away from discussions of a sale within weeks.

Dark Horse rises

Around the same time, Riseborough said major client jobs began falling apart under Mahon’s supervision, including one that caused Turtle Transit to miss a deadline for the first time in company history.

In fall 2022, Riseborough asked Caron to draft a formal business plan to make sense of the company's declining sales. He quit the following week instead, Riseborough said.

By September 2023, Troest had worked remotely for an extended stretch before relocating to Florida. When staff tried to process payroll in her absence, Riseborough said none of the passwords worked. He hired Marlborough-based forensic accountant Denise Cataldo to dig deeper.

Cataldo’s review, which later informed a law enforcement investigation, found Troest had embezzled roughly $800,000 from the company between 2016 and 2023 through payroll manipulation, forged checks, and personal credit card charges, according to a court filing by the Middlesex District Attorney's Office.

“I would meet with her every Monday,” Riseborough said. “We’d go through cash receivables, expenses. But Kim was just really good at hiding that stuff.”

After she left the firm, Riseborough found out Troest, then known as Kimberly Barrett, had a record of theft-related convictions: Middlesex Superior Court records show she pleaded guilty in 2002 to multiple larceny and conversion counts and received 10years of probation, while a separate Worcester County case resulted in guilty pleas in 2011 on six larceny counts and an order to pay $278,898 in restitution.

Riseborough said the gravity of the situation became apparent when Cataldo found a credit application listing Troest, Caron, and Mahon as partners in Dark Horse Experiential.

As the business unraveled, Riseborough and his wife withdrew retirement funds and personal savings and borrowed from friends. In January 2024, he sold the Hudson headquarters for $2.7 million.

Legal cases

In June a Middlesex County grand jury indicted Troest on 11 counts, Caron on two counts, and Mahon on one count. The Middlesex District Attorney's Office alleged in court documents Troest embezzled approximately $800,000 from Turtle Transit, and she and Caron committed mortgage fraud by submitting a falsified income verification letter to a lender.

The office alleges Troest, Caron and Mahon conspired to defraud the Massachusetts Department of Unemployment Assistance of tens of thousands of dollars by falsely claiming Caron and Mahon had been terminated from Turtle Transit, when in fact they were already working for a company they jointly owned.

Lopez has not been charged criminally, though she remains a defendant in the civil case.

Riseborough and Turtle Transit filed a civil complaint July 8 in Middlesex Superior Court against Troest, Caron, Mahon, Lopez, and Dark Horse Experiential. Both the district attorney's office and Riseborough’s civil complaint allege the four former employees secretly formed their company while still working for Turtle Transit.

The 14-count lawsuit alleges embezzlement, fraud, breach of fiduciary duty, trade secret misappropriation, defamation, and violations of the state's unfair business practices law.

Riseborough said he was under the impression Dark Horse and its employees thought they were in the clear.

“I don’t even think they even know what’s going on,” he said. “I think they believe they’ve gotten away with it.”

Eric Casey is the managing editor at Worcester Business Journal, who primarily covers the real estate and banking & finance industries.