1978 film Grease and its 1982 sequel Grease 2. "Luxurious" is a 1990s-inspired R&B song that lyrically talks about the desire to be rich in love, simultaneously comparing Stefani's lover with luxuries. The seventh track, "Harajuku Girls", is a synth-pop song that was described as a tribute to Tokyo's street culture, produced by Jimmy Jam and Terry Lewis. "Crash" is an electroclash song that uses automobile metaphors to describe a relationship. "The Real Thing" was described as a vintage Europop song, and features guest appearances from New Order vocalist Bernard Sumner and bassist Peter Hook. The next track, the synth-pop song "Serious", drew comparisons to Madonna's work during the early 1980s. A music video was produced for the song, but it was never officially released, although a snippet of the video surfaced on YouTube in October 2006. "Danger Zone", an electro-rock song, was widely interpreted to be about Stefani's husband Gavin Rossdale having an illegitimate daughter; however, the song had been written before the discovery. The closing track "Long Way to Go" is an outtake from André 3000's album The Love Below (2003). The song discusses interracial dating and uses a sample of Martin Luther King Jr.'s 1963 speech "I Have a Dream". Promotion Stefani embarked on the Harajuku Lovers Tour on October 16, 2005, to promote Love. Angel. Music. Baby. The tour consisted of only one leg, running for 42 dates across North America, ending on December 21, 2005. The hip hop group the Black Eyed Peas, rapper M.I.A., and singer Ciara accompanied Stefani as opening acts for her tour. The tour was met with varying responses from contemporary critics, who despite praising Stefani's vocals, were critical of other aspects of the show such as its musical material. According to Billboard, the tour grossed $22 million from 37 shows, 20 of which sold out. A video album of the concert titled Harajuku Lovers Live was released on DVD on December 4, 2006. Additionally, a remix EP titled Love. Angel. Music. Baby. (The Remixes) was released on November 22, 2005, including remixes of "Luxurious", "Cool", "Hollaback Girl", and "What You Waiting For?". Singles "What You Waiting For?" was released as the lead single from Love. Angel. Music. Baby. on September 28, 2004. The single peaked at number 47 on the Billboard Hot 100, and was commercially successful overseas, topping the chart in Australia and reaching the top 10 in several