Massi had been playing with several bands before he joined The Four Lovers in 1958, including some groups that featured future Four Lovers members Frankie Valli and Tommy DeVito. After the group evolved into the Four Seasons, they performed such hits as "Sherry," "Dawn (Go Away)," and "Rag Doll." He was responsible for most of the group's vocal arrangements. Massi left the Four Seasons in 1965 and was replaced temporarily by Charles Calello who in turn was replaced by Joe Long.
Music wasn't Nick's only talent. Some of his paintings can be viewed at http://www.nickmassiart.com/1.html. He was also very talented at billiards.