"Inner Urge" is Joe Henderson's fourth record as a leader. The album was released in 1966 on Blue Note Records. The session features Henderson along with pianist McCoy Tyner, drummer Elvin Jones and bassist Bob Cranshaw. The title track has become a jazz-standard. "Isotope" is a tribute to Thelonious Monk and his use of musical humor. The music on this album pushes bop formulas as far as they could be pushed. This cd is an absolutely essential listen and a major masterpiece.