The tale begins in 1900 as Roberto Colombo, an Italian-American attorney living in the Little Italy, is killed by gangsters as he informs a police officer about an attempt of money extortion. His widow and son return to Italy where the former dies.
Cut to 1908, his son Giovanni Colombo (Gene Kelly) returns to New York City determined to conduct a vendetta against the men who had killed his father.
He meets up with childhood friend Isabella Gomboli (Teresa Celli) and police detective Louis Lorelli (J. Carrol Naish), who try to dissuade him.
Giovanni and Isabella rally people in Little Italy against the Black Hand racket, but that movement is dealt a set-back when Giovanni is attacked and his leg is broken. Recovering from his injury, Giovanni decides to study law as his father had. The bombing of a local store convinces Giovanni to put his studies aside and help track down the perpetrators.
At the trial, a key witness is intimidated and refuses to testify, but the defendant is deported when police in Naples identify him as a fugitive from justice.
After the deportation, Lorelli travels to Italy to identify other Italian criminals. He is killed after mailing his report to Giovanni in New York City. To prevent the list from reaching the authorities, the gangsters kidnap Isabella’s young brother.
In the end, after the gangsters get the list and the boy is released, Giovanni escapes and saves the list by igniting a bomb.
Cast
Gene Kelly as Giovanni E. “Johnny” Columbo
J. Carrol Naish as Louis Lorelli
Teresa Celli as Isabella Gomboli
Marc Lawrence as Caesar Xavier Serp
Frank Puglia as Carlo Sabballera
Barry Kelley as Police Captain Thompson
Mario Siletti as Benny Danetta / Nino
Carl Milletaire as George Allani / Tomasino
