Giancarlo's mother was an African-American opera singer from Alabama and his father was a Neopolitan stagehand from Naples, Italy. He was born in Copenhagen because his mother was appearing there in a nightclub on a split bill with Josephine Baker. During his childhood, Giancarlo lived in Italy and attended military school. He recalls that he quickly learned to take care in the way one dressed, mostly from his father's fastidiousness. After living in Europe (Rome, Hamburg) and Cleveland, his family settled in Manhattan in 1964. His parents later divorced.
Giancarlo ventured very early on into acting and theatre. At the age of 7, he auditioned for a Broadway musical and won the role as a slave child in "Maggie Flynn" in 1966. The family had little money at the time, but they were able to get an agent. He continued Broadway work throughout the 1960s and 1970s. At one point he appeared alongside Steven Bauer and Gary Sinise. He then ventured into television and movies, his credits numerous and his work multifaceted. Giancarlo most notably starring in several television dramas (Bakersfield, P.D., Homicide: Life on the Street, and The $treet). Some of his most notable film roles include those in Do The Right Thing (1989), School Daze (1988), The Usual Suspects (1995), Malcolm X (1992), Nothing To Lose (1997), Ali (2001), The Box (2007).
More recently, Giancarlo became a pivotal cast member on the television show Breaking Bad. After thrilling audiences as Gus Frings for several years, he has gained a popularity that has landed him on several new shoes including Once Upon a Time, NYC 22, and Revolution.
Giancarlo was married to Joy McManigal and is the father of four children, three of them: Shayne (b. 1997), Kate (b. 1998), and Ruby (b. 2004). These days, Giancarlo also directs and produces feature films, for example Gospel Hill (2008) and This Is Your Death (2012) and has aspirations of getting feature films to the box office. Esposito is now a cast of the new series Revolution.