Viva Las Vegas (1964) is an American romantic musical motion picture co-starring American singers Elvis Presley and Ann-Margret. The movie is regarded by fans as one of Presley's best and is noted for the on-screen chemistry between Presley and Ann-Margret. However, according to a contemporary review in the New York Times, "Viva Las Vegas the new Elvis Presley vehicle, is about as pleasant and unimportant as a banana split." Notwithstanding, "Viva Las Vegas" has become one of Presley's most iconic phrases.

The chemistry between the two stars was apparently real during the filming. Presley and Ann-Margret allegedly began an affair which received considerable attention from gossip columnists and led to a showdown with a worried Priscilla Beaulieu. In her 1985 book, Elvis and Me, Priscilla described the difficulties she experienced when the press announced that Ann-Marget and Elvis were engaged to be married. However, there may have been other reasons for the great publicity campaign about the romance between Elvis and Ann-Margret during the filming of Viva Las Vegas and the following weeks. It primarily helped to increase the popularity of the young Hollywood beauty. In her memoir, Ann-Margret only refers to Presley as her "soulmate", but very little is revealed about their long-rumored romance. In his critical study on the "dream machine" that publicists, tabloid newspapers, journalists, and TV interviewers use to create semi-fictional icons, often playing with inauthenticity, Joshua Gamson cites a press agent "saying that his client, Ann-Margret, could initially have been "sold ... as anything"; "She was a new product. We felt there was a need in The Industry for a female Elvis Presley."

In addition, the filming produced unusually-heated exchanges between Presley's manager Colonel Tom Parker (who is not shown as "Technical Advisor" in the opening credits for this film) and the movie's director, the highly experienced George Sidney, concerning the time and effort allotted by the cinematographer, ostensibly on Sidney's orders, to the musical scenes involving Ann Margret, which included views from many different angles, re-takes and the use of several cameras for each shot.

Presley's screen charisma was nevertheless there for anyone to see. The scene in which he delivers the title song remains the only one in his career to depict him performing an entire song, in one uncut take, and as shot by the lens of a single camera.

Lucky Jackson arrives in town with his car literally in tow ready for the first Las Vegas Grand Prix - once he has the money to buy an engine. He gets the cash easily enough but mislays it when the pretty swimming pool manageress takes his mind off things. It seems he will lose both race and girl, problems made more difficult by rivalry from Elmo Mancini, fellow racer and womaniser. Perhaps some singing will help. Written by Jeremy Perkins

Race car driver Lucky Jackson goes to Las Vegas to earn money to pay for a new engine for his motor car. Working as a waiter, he still finds the time to court young Rusty Martin. Written by Mattias Thuresson