As a member of the Four Seasons, Valli's number-one hits include "Sherry" (1962), "Big Girls Don't Cry" (1962), "Walk Like a Man" (1963), "Rag Doll" (1964) and "December, 1963 (Oh, What a Night)" (1975).

Valli was born Francesco Stephen Castelluccio,[10] on May 3, 1934,[11] to an Italian family in the First Ward of Newark, New Jersey; he is the eldest of three sons.

Other sources gave his year of birth as 1934, such as the Bear Family Records release The Four Lovers (BCD 15424) and a 1965 mug shot, available through The Smoking Gun.

[21] Geoff Herbert explains, "Frankie said in 2010 that Jean took him to meet music publishers Paul and Dave Kapp, telling them he was her brother.

In late 1952, the Variety Trio disbanded and Valli and Tommy DeVito became part of the house band at The Strand in New Brunswick, New Jersey.

Valli recorded his first single, "My Mother's Eyes", in 1953, a cover of the 1929 George Jessel song from Lucky Boy, with his stage name "Frankie Valley."

Around this time, Valli, Majewski and Tommy DeVito left the house band at The Strand and formed The Variatones with Frank Cottone and Billy Thompson.

[24] The Four Lovers continued, with Valli, DeVito and an ad hoc lineup that variously included Macioci (by then also pursuing a solo career as "Nickie Massey"[25]), Charles Calello and Hollywood Playboys keyboardist Hugh Garrity.

[24] In 1959, after being introduced at a gig in Baltimore by mutual friend Joe Pesci, Royal Teen Bob Gaudio became a member.

During the 1960s, Gaudio and his songwriting partner Bob Crewe worked with Valli to craft solo recordings, with varying degrees of success.

He used the opportunity to transition away from the power falsetto that had made Valli and the Four Seasons famous, singing in a natural tenor voice.

[31]) "You're Ready Now", a Valli solo recording from 1966, became part of the Northern soul scene and reached number eleven on the UK Singles Chart in December 1970.

"The Night" originally released in 1970 also became a huge Northern soul hit and as a result it reached number seven on the UK Singles Chart in 1975.

As part of that agreement, Valli—with great reluctance—ceded some of the lead vocals for the group to new band members Gerry Polci and, to a lesser extent, Don Ciccone.

[10][39] From March 2016 to January 2017, "Frankie Valli and the Four Seasons" were touring the US, scheduled to play small-to-mid-size venues such as the Silver Legacy Casino in Reno, Nevada, the Celebrity Theatre in Phoenix, Arizona and the County Fair in Bloomsburg, Pennsylvania.

[46] On the November 21, 2014, episode of Hawaii Five-0 entitled "Ka Hana malu (Inside Job)", Valli played mysterious lawyer Leonard Cassano, who was engaged to Carol Burnett's character, Aunt Deb.

[43] Valli has a restraining order against his son, Francesco Jr., an actor, due to an opiate addiction and threats of violence against his father and brothers.

[53] One issue in Valli's third divorce went up on appeal to the Supreme Court of California: whether a life insurance policy purchased in 2003 was community property.