
Once a photographer by day, spy by night, Matt Helm is now a happily retired secret agent, shooting photos of glamorous models instead of guns and enjoying a close relationship with his assistant, the lovely Lovey Kravezit. But then his old boss, Macdonald, coaxes him back to the agency ICE to thwart a new threat from the villainous organization Big O.

The sinister Tung-Tze is masterminding a diabolical scheme to drop a missile on an underground atomic bomb test in New Mexico and possibly instigate a nuclear war in the process. Helm's assignment is to stop him, armed with a wide assortment of useful spy gadgets, plus the assistance of the capable femme fatale, Tina, and the seemingly incapable Gail Hendricks, a beautiful but bumbling possible enemy agent.

Along the way, Helm is nearly sidetracked by a mysterious knife-wielding seductress and he witnesses the murder of a beautiful Big O operative, the sultry striptease artist Sarita.

In the end, Helm prevails, with Gail by his side as he all but singlehandedly destroys Tung-Tze's evil enterprise and plot to rule the world.

The film was the first of four produced between 1966 and 1969 starring Martin. Whereas Hamilton's books were generally serious spy novels about a former Second World War assassin who is recruited to continue killing for an American government agency, the film versions were lighthearted spy romps spoofing the James Bond series in the same spirit as Our Man Flint, which was released the previous month. The Helm series has been cited as one of the principal inspirations for the Austin Powers spy comedies of the 1990s and early 2000s.
Dean Martin as Matt HelmStella Stevens as Gail HendricksDaliah Lavi as TinaVictor Buono as Tung-TzeArthur O'Connell as WigmanRobert Webber as Sam GuntherJames Gregory as MacdonaldNancy Kovack as BarbaraRoger C. Carmel as AndreyevCyd Charisse as SaritaBeverly Adams as Lovey KravezitRichard Devon as DominoFilm producer Irving Allen had been in partnership with Albert R. Broccoli in Warwick Productions, who released through Columbia Pictures. Broccoli wanted to buy the rights to the James Bond series of novels, but Allen was not interested. The partnership broke up, Broccoli went into partnership with Harry Saltzman and United Artists on the Bond films and enjoyed tremendous success.
Allen decided to make his own spy series. He optioned film rights to the Matt Helm novels in 1964 in association with Columbia Pictures. The Silencers was to be the first. Dean Martin signed to play the lead.
Director Phil Karlson had the idea to make the film in a tongue-in-cheek style. Comedy writer Herbert Baker revised Oscar Saul's original script. Dean Martin was a co-producer of the Helm series. Moss Mabry provided the costumes, except for Martin's Sy Devore suits.
Richard Levinson and William Link also worked on the script of this and The Ambushers.
Released at the height of James Bond mania, The Silencers was a major box office hit in 1966, earning $7 million in North American rentals that year.
There were three follow-up films, including Murderers' Row (also released in 1966), The Ambushers (1967) and The Wrecking Crew (1969). A fifth film, The Ravagers, was announced, but never produced.
Elmer Bernstein provided the score, with Vikki Carr singing the title song and "Santiago." Two soundtrack albums were released — Bernstein's original score on an RCA Victor album that does not feature any artwork of Dean Martin, and a Reprise album by Martin singing several songs that were featured in the film, along with some instrumentals by the Mike Leander Orchestra.
A scopitone video of the title song was sung by Joi Lansing. Carr's version of the title song was also used on the soundtrack of the film Confessions of a Dangerous Mind.
Recently, English label Vocalion have issued full movie soundtrack on a CD, catalog number CDLK4573.
The Silencers borrows a plot element from the first Helm novel, Death of a Citizen, as it begins with the agent being coaxed out of retirement. Helm's mission is to stop an evil organization called "BIG O" (the Bureau for International Government and Order) from their plan of "Operation Fallout": diverting an American missile into an underground atomic bomb testing site in New Mexico.