The Gallstones were a singing trio comprised of two brothers and their sister Imma. They achieved some popularity nationwide. They became involved with Dick Tracy and the MCU during 1976.
When Lizz was abducted by contract killer known as Pucker Puss, he held her on a luxury boat stolen from The Gallstones. The Gallstones put on daily shows for Lizz and Tracy when they were hospitalized after being injured during Lizz's escape. A patient in the hospital who had her gallstones removed gave them to the trio as a souvenir.
Later, Sam Catchem arrested a teenage thief named Cupie and discovered that his car trunk contained dozens of bootleg Gallstones vinyl albums. This led to an MCU investigation that implicated the group's long-time manager Bolo, who pirated the albums and sold them on the black market for personal profit.
Imma was engaged to marry Bolo, but Tracy convinced the group of Bolo's guilt, and they agreed to fire him and bring legal action.