Press-ready copy
Short press biography
DoubleU is the recording name of William Kirby Hartman, a Florida-born, Kentucky-raised artist whose work turns grief, service, incarceration, and rebuilding into direct, narrative-driven music. Adopted at 13 months old and raised in Hopkinsville, Hartman lost his adoptive father, retired Air Force Master Sergeant Nick Hartman, at age ten. He began playing trumpet the following year and continued through high school.
Hartman started making music during inpatient treatment at Youth Villages Inner Harbour, where recording became a way to cope. His first official release, “Two of Us,” arrived in October 2021, followed by the album Faded 405. He later served in the U.S. Army as a 68W Combat Medic, training at Fort Sill, Fort Sam Houston, and Fort Benning before leaving the service in October 2023.
After a turbulent period that included incarceration, DoubleU returned to music with a sharpened purpose. His 14-track concept album Cold Case uses a cold-case noir world to explore isolated pain and the struggle to be seen as more than a record, label, or worst chapter. His goal is simple: if the music helps one listener feel less alone—even a fraction—it has done its job.
Artist statement
“I make music from the parts of life people usually hide. Cold Case is about isolated pain—what it feels like to be reduced to a file, a charge, a memory, or somebody else’s version of you. I cannot change what another person has lived through, but if they hear my story and feel less alone, even for a minute, that means something. DoubleU comes from the W in William. Some days it stands for winning. Some days it stands for the weight of the world. The music lives between those two meanings.”— DoubleU
Official biography
Long-form biography
Music became a way to survive what words could not hold
DoubleU is the recording name of William Kirby Hartman, an artist whose music carries the sound of a life rebuilt in public: grief, service, incarceration, love, and the determination to make another person feel less alone.
Born April 6, 2004, in Duval County, Jacksonville, Florida, Hartman was adopted at 13 months old by his maternal biological great-aunt and raised in Hopkinsville, Kentucky. His stage name comes directly from the first letter of William: W, spoken aloud as “DoubleU.” He has turned that spelling into a question that follows his work—does the W mean winning, or the weight of the world?
Music did not begin for Hartman as a branding exercise or a career plan. He started creating while receiving inpatient treatment at Youth Villages Inner Harbour, where he met a small group of other young people making music. The process became a way to cope and to give shape to experiences he could not carry silently. “Two of Us” and “Real Life Trauma” were created in that environment. “Two of Us,” released in October 2021, became his first official release.
His childhood was shaped by family, discipline, and sudden loss
Hartman remembers his early childhood as happy. He grew up alongside three full biological siblings and within a much larger blended family. The central father figure in his life was his adoptive father and biological great-uncle, Nick Fairbanks Hartman, born July 15, 1945, in Whitwell, Tennessee.
Nick served 20 years in the United States Air Force as a driver, refueler, and teacher, retiring as a Master Sergeant. Hartman also remembers him as a Master Mason, a doctorate holder, and the owner-operator of a heavy-haul, cross-country trucking company that worked with Daily Express Inc. Among the oversized loads that became family lore was a dinosaur display Nick transported to the West Coast. To Hartman, these were not résumé lines; they were the scale of the man who raised him.
That stability ended when Hartman was ten. During the family’s annual fall camping trip at Land Between the Lakes, Nick suffered a massive heart attack on the night of October 9, 2014. He died at Marshall County Hospital on October 10. The loss changed the emotional climate of the household. Hartman describes his mother as physically present afterward but mentally overwhelmed by grief—so broken, in his words, that she seemed to let go.
Trumpet gave grief a structure
A year after Nick’s death, in sixth grade, Hartman began playing trumpet. He stayed with it through high school. The instrument gave him discipline and a durable connection to music before he ever considered becoming a recording artist.
The music around his childhood crossed genres and generations: Dolly Parton, Elvis Presley, Blake Shelton, Reba McEntire, Michael Jackson, and Bruno Mars. That mix helps explain why DoubleU’s work is less interested in staying inside one lane than in finding the right language for a feeling.
SERVICE, CONSEQUENCE & REBUILDING
The Army carried him from Kentucky to Oklahoma
Hartman served in the United States Army as a 68W Combat Medic. His training path took him through basic training at Fort Sill, Oklahoma; advanced individual training at Fort Sam Houston, Texas; and Airborne training at Fort Benning, Georgia, before returning him to Fort Sill. The Army brought him to Oklahoma City and gave him a new geography, a new set of responsibilities, and another chapter built around endurance.
He left the Army in October 2023. The transition that followed was turbulent and would become inseparable from the story he later chose to tell through music.
His legal history is part of the story, not the whole identity
Hartman was incarcerated beginning February 12, 2024. He was released from prison on January 2, 2025, later returned to jail, and was released again in August 2025. Hartman describes the conviction connected to that period as wrongful. He has chosen not to erase this history from his public biography, but neither does he allow it to become the only frame through which his life or work is understood.
For DoubleU, honesty means acknowledging consequence, isolation, and the damage of being reduced to a case or a label. It also means insisting that a person can be more than the worst season of his life. That tension—between the record and the human being inside it—runs directly into the world of Cold Case.
Cold Case turns isolation into witness
Faded 405 was DoubleU’s first album. Cold Case, his 14-track cold-case noir concept album, pushes his work into a more focused narrative world. The project uses the language of evidence, interrogation, frozen scenes, and unresolved files to describe the experience of carrying pain in isolation.
The purpose is not simply confession. Hartman wants the record to reach people who have endured some version of what he has lived through and make them feel recognized. Cold Case is built on the belief that even a small measure of connection can matter when somebody believes they are alone.
“Cold Case is about going through that isolated pain. Hopefully I can help someone—even a fraction—especially if they went through or experienced some of what I did.”— DoubleU
A new family chapter began after release
In September 2025, shortly after his release from jail, Hartman met Katelynn. They married on March 2, 2026. Their family includes Katelynn’s daughter, and they are expecting a child in April 2027. The relationship belongs in his public story not as a tidy ending, but as evidence of a life continuing to move: from survival toward responsibility, partnership, and the possibility of building something steadier.
DoubleU’s story does not ask to be cleaned up. It asks to be heard whole. The music comes from the same place as the name: the pressure of the weight, the decision to keep moving, and the possibility that the W can still mean winning.
Selected milestones
- “Two of Us” releasedFirst official release
- U.S. Army service endsEnd of service
- Released from prisonRebuilding begins
- Released from jailReturns to life outside
- Marries KatelynnFamily chapter
- Cold Case in development14-track concept album