Leopoldo Ballesteros Marín is a Spanish actor born on March 7, 1959, in Granada, Spain, with a extensive career in theater, television, and voice acting. His professional background includes a strong foundation in dramatic arts, having studied at the Real Conservatorio de Valencia, complemented by further training in voice and theater. In addition to his performance work, he has also dedicated time to teaching theater classes for children in various schools within the Community of Madrid.

Ballesteros is widely recognized for his prolific work in dubbing, particularly in animation. He is notably the Spanish voice of the character Starscream across multiple installments of the Transformers franchise. His portrayal of the iconic Decepticon includes the animated series Transformers: Armada, Transformers: Energon, Transformers: Cybertron, and Transformers: Prime. He also lent his voice to the character in several video game adaptations, such as Transformers: The Game, Transformers: Revenge of the Fallen, Transformers: War for Cybertron, and Transformers: Dark of the Moon.

Another significant role in his voice acting career is that of Shanks in the long-running anime series One Piece. He has voiced the character for many years, a role that includes his participation in the 2022 feature film One Piece Film Red, for which he was featured in promotional events with the cast. His contribution to the series extends well beyond this single character, as he has provided voices for numerous other figures in the One Piece universe, including Merry, Calú, Fullbody, Master Koshiro, King Cobra Nefertari, and Octo, among many others.

His voice work spans a wide variety of other animated series and video games. He has voiced characters in MegaMan NT Warrior, such as PharaohMan and Doctor Hikari, and in Detective Conan, where he played roles including Doctor Eto and the father of Shin'ichi Kudo. In the European Spanish dub of Thomas & Friends, he voices characters like Duck, Flying Scotsman, and Harvey from the seventeenth season onward. His video game credits also include the role of Alister Fletcher in Tomb Raider: Legend and Tomb Raider: Underworld, as well as contributions to major franchises like Call of Duty and Assassin's Creed.

Beyond his voice work, Ballesteros has an extensive filmography as an on-screen actor in Spanish television. He has appeared in numerous popular series, including Médico de familia, Hospital Central (where he played Dr. Polo), Amar en Tiempos Revueltos (as Rogelio Buendía), Periodistas, and Compañeros. His theatrical career includes performances in works such as De repente, el último verano by Tennessee Williams and Tres sombreros de copa by Miguel Mihura.