In 1949, Montenegro was cast in his first film role in the World War II drama
Capas. The following year, he was cast by director
Manuel Conde in his first leading role, in
Apat na Alas (1950). '', Montenegro portrays the titular role. During the 1950s, Montenegro was among the mainstays of
LVN Pictures studio headed by
Doña Sisang de León. He was often cast in
costume dramas and action films, dabbling occasionally in comedy roles. He portrayed heroic leads in such historical films as
Dagohoy (1953),
Lapulapu (1955),
Kilabot ng Makiling (1959) and
Alyas Sakay (1959). Throughout his career, Montenegro would be nominated for a total of three
FAMAS acting awards, including two Best Actor nominations. As he aged, Montenegro found himself cast in character roles. Among his more notable later roles was in
Mike de Leon's
Itim (1976), for which he received a Best Supporting Actor nomination from the
Gawad Urian. His last film was
Madonna: Ang Babaeng Ahas, filmed in 1988, but it was released posthumously in 1991. ==Political views==