Let's Do It, Let's Fall in Love

"Let's Do It, Let's Fall in Love" (also known as "Let's Do It (Let's Fall in Love)" or simply "Let's Do It") is a popular song written in 1928 by Cole Porter. It was introduced in Porter's first Broadway success, the musical Paris (1928) by French chanteuse Irène Bordoni for whom Porter had written the musical as a starring vehicle.

Bordoni's husband and Paris producer Ray Goetz convinced Porter to give Broadway another try with this show. The song was later used in the English production of Wake Up and Dream (1929) and was used as the title theme music in the 1933 Hollywood movie, Grand Slam starring Loretta Young and Paul Lukas. In 1960 it was also included in the film version of Cole Porter's Can-Can.

The first of Porter's "list songs", it features a string of suggestive and droll comparisons and examples, preposterous pairings and double entendres, dropping famous names and events, drawing from highbrow and popular culture. Porter was a strong admirer of the Savoy Operas of Gilbert & Sullivan, many of whose stage works featured similar comic list songs.

The first refrain covers human ethnic groups, the second refrain birds, the third refrain marine life, the fourth refrain insects and centipedes, and the fifth refrain non-human mammals.

One commentator saw the phrase Let's do "it" as a euphemistic reference to a proposition for sexual intercourse. According to this argument, Let's do it was a pioneer pop song to declare openly "sex is fun". According to it, several suggestive lines include a couplet from verse 4: "Moths in your rugs do it, What's the use of moth-balls?" and "Folks in Siam do it, Think of Siamese twins" (verse 1) and "Why ask if shad do it? Waiter, bring me shad roe" (verse 3) and "Sweet guinea-pigs do it, Buy a couple and wait" (verse 5). There is also a report that Porter's original version included the even more risqué line, "Roosters with a doodle and a cock do it". If true, this was probably replaced by one of the lines in the verse 2 couplet "Penguins in flocks, on the rocks, do it, Even little cuckoos, in their clocks, do it."

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