Giacomo Castellano began studying guitar at the age of 14 and attended various music schools in Florence.
In 1987, he founded the Progressive Rock band "Time Escape," and the following year, he decided to move to Hollywood, where he enrolled at the Musicians Institute.
In the early 1990s, he started working as a studio and live session guitarist, collaborating over the years with well-known Italian artists such as Claudio Simonetti, Paolo Vallesi, Raf, Irene Grandi, Gianluca Grignani, Gianna Nannini, Elisa, Vasco Rossi, Noemi, Piero Pelù, and even Adriano Celentano, with whom he also worked on the TV show Rockpolitik.
Since 2000, he has also worked in Spain with Mónica Naranjo, Edurne, David Demaria, Rosana Arbelo, and other artists, eventually landing a role in the musical We Will Rock You, written by Queen.
As a solo artist, Giacomo has released his album Cutting Bridges, the Racer Café project (together with Gianni Rojatti), and several singles, which have been published over the years up to the present day.
Castellano has also been active in teaching, and his books have become "cult" works in modern guitar education: Metodo per chitarra Heavy Metal and La chitarra ritmica Rock-Metal, followed by other collaborations on various manuals with other authors.
In 2024, he joined Premiata Forneria Marconi (PFM) after Marco Sfogli and Franco Mussida.
Giacomo is also known for being the producer and director of all his videos, as well as those he regularly produces for others.