Cole Porter, composer of "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 famous "list songs", it features a string of suggestive and droll comparisons and examples, preposterous pairings and double entendres, dropping famous names and events, drawing unexpectedly 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.
One commentator saw the phrase Let's do "it" as a euphemistic reference to a proposition for a 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's 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."
The nature of the song, "Let's Fall in Love," is such that it has lent itself over the years to the regular addition of contemporary or topical stanzas. For example, in 1955 the line "Even Liberace, we assume, does it" was added by Noël Coward in his cabaret performance of the song although Coward's lyrics were entirely and completely rewritten as a topical piece, with none of Porter's lyrics remaining.
The song has been revived many times since 1928, although usually with only a limited portion of the original lyrics. A punk rock version performed by Joan Jett and Paul Westerberg was used as the theme song in the 1995 movie Tank Girl, and later in a more classical version in a musical revue number within the film. In the revue, the song is at first performed by stage actress Ann Magnuson, but is taken over by star Lori Petty after she places duct tape over Magnuson's mouth. It was originally recorded with Joan Jett and Greg Graffin, but Atlantic Records did not want them using Graffin so they deleted his voice and recorded Westerberg's. Joan Jett and Greg Graffin's version of "Let's Do It" was eventually released in 2000 on the compilation CD Laguna Tunes (Blackheart Records).
"So let's do it, just get on a plane and just do it // Like the birds and the bees and get to it"
Brazilian singers Chico Buarque and Elza Soares recorded a Portuguese adaptation by Carlos Rennó, "Façamos - Vamos Amar" on Buarque's 2002 album "Duetos". It adds even more nations, animals and groups.
The song also influenced the Canadian indie-rock group Mother Mother in their song Let's Fall In Love.
Pablo Bubar  reintroduced "Let's Do It (Let's Fall in Love)" in one of the musical romance sketches of "Pablo the Romantic" from "Boom Town", broadcast by BBC Three (UK, 2013). This version includes the piano music of Ross Leadbeater .
Racial lyrics controversy
In Porter's publication from 1928, the opening lines for the chorus carried three derogatory racial references: Chinks, Japs, and Laps.
Chinks do it, Japs do it, up in Lapland little Laps do it...
The original line can be heard in several early recordings of the song, such as a recording made by Dorsey Brothers & their Orchestra (featuring a vocal by a young Bing Crosby),Rudy Vallée, both in 1928, and a version of the song by the singer and well-known Broadway star Mary Martin (with Ray Sinatra's orchestra), recorded in 1944. Another example is Billie Holiday, in 1941. Peggy Lee with the Benny Goodman orchestra recorded a version in 1941 with these lyrics (see the CD "The Essential Benny Goodman" published by Columbia/Bluebird/Legacy (88697 09491 2)).
Porter changed the opening to the now famous refrain: "Birds do it, Bees do it" when he realized that the line was offensive.
Eartha Kitt with Henri René and his orchestra. Recorded in New York City on October 5, 1951. It was released by RCA Victor Records as catalog number 20-5737 (in USA) and by EMI on the His Master's Voice label as catalog number B 10778. The song was also released on the LP That Bad Eartha (1953)
James Newman - Skins (Newman performed the song (as his character Tony) in the episode "Tony" of the U.S. version of the U.K. drama Skins.)
Yves Heck - Heck played the physical role while Conal Fowkes provided the voice as Cole Porter in the 2011 Woody Allen film Midnight In Paris
Wonder Pets—In the episode "Save the Puppy", they sang a spoof of the song about how everyone needs to "wee-wee, pee-pee, tinkle" using the lyrics "Dogs do it, frogs do it, even funny winking hogs do it...".
The Sesame Street song "Let's Lay an Egg" is a spoof of the song, using the lyrics "Snails do it, slugs do it. Even tiny Twiddlebugs do it!...".