The unnamed tattoo artist known as Uncle was an elderly man. He was bald, wore dark glasses, and typically smoked cigars. He had tattoos on his head and limbs.
On the occasion of his 100th birthday, Uncle bragged to his family that he was most likely the world's oldest living tattoo artist. He also related the story of how he had tattooed a map onto the head of a nine-year-old orphan girl (who later became known as Gravel Gertie) many years before.
- Uncle's name was never specified. He was addressed as "Uncle" by the relatives at his birthday party, and he was identified by that title on the back cover of The Complete Dick Tracy Vol. 26.