N-Dubz were a British hip hop group from Camden Town, London.
 The group consisted of members Dappy, Tulisa and Fazer.
Costadinos Contostavlos (born 11 June 1987), better known by his stage name Dappy, is an English singer, songwriter, rapper, and actor.
 He is best known for being the lead singer of the Camden-based grime trio N-Dubz, with his cousin Tulisa, and Fazer.
 He was known for his slightly unusual dress sense and his love for what he describes as "eye-catching headwear".
 His trademark was wearing a selection of woolly chullos (sometimes referred to as "Dappy hats"), turning up one or both of the ear-flaps of the hat.
Rock Star is a television series produced by Mark Burnett, David Goffin, and Lisa Hennessy in which aspiring singers from all around the world competed to become the lead singer of a featured group.
 It debuted on CBS on July 11, 2005, to mediocre ratings.
 The show was hosted by television personality and commercial spokeswoman Brooke Burke and Jane's Addiction & Red Hot Chili Peppers lead guitarist Dave Navarro.
 In Australian band INXS chose J.D. Fortune as their new lead singer.
 For , the band Rock Star Supernova chose Lukas Rossi as the lead singer of their new supergroup.
Timothy Robert "Tim" Maurer (born October 10, 1980) is an American singer, best known as the former lead singer of third-wave ska band Suburban Legends.
 He has left the band on two separate occasions.
 The first was in 2000 after the recording of Origin Edition.
 He rejoined the band in early 2002 after his replacement singer Chris Batstone left the band.
 He officially left the band again in September 2005 after the band's third consecutive appearance on the Jerry Lewis MDA Telethon, performing a new song entitled "Moving Closer."
 The band's former trumpet player, Vincent Walker, rejoined the band for the performance, then took over as lead singer afterward.
 Maurer returned for a final performance with the band on November 29, 2005 at Huntington Beach High School for a benefit show for the Ryan Dallas Cook Memorial Fund, which was set up following the death of Suburban Legends' trombonist Dallas Cook.
Barbados is a Swedish dansband, formed in 1992, who have had several Swedish chart successes.
 The band, with lead singer Magnus Carlsson, became widely known after their second place in Melodifestivalen 2000.
 The band has replaced lead singer three times.
 First Magnus Carlsson left the group in 2002 and later became a member of the group Alcazar.
 Mathias Holmgren, a former Fame Factory student was the new lead singer, but was forced to leave the band in 2004.
 Chris Lindh replaced him, before leaving the band in 2007.
 The current lead singer is Björn Lagerström.
The lead vocalist, main vocalist, lead vocals or lead singer in popular music is typically the member of a group or band whose voice is the most prominent in a performance where multiple voices may be heard.
 The lead singer either leads the vocal ensemble, or sets against the ensemble as the dominant sound.
 In vocal group performances, notably in soul and gospel music, and early rock and roll, the lead singer takes the main vocal part, with a chorus provided by other band members as backing vocalists.
Sennie "Skip" Martin III (born June 25, 1957, in San Francisco, California, U.S.) is an American musician, now based in Las Vegas.
 He is a lead vocalist, trumpet player, songwriter and producer who was formerly lead vocalist for Kool & The Gang (1987–2007) and the Dazz Band.
 Before those groups he was lead singer for the East Wind Band and then he was lead singer for the Mighty Generation Band.
 With the Dazz Band he won a Grammy Award for the song “Let It Whip”.
Alexander Martin Barr (born January 21, 1968) has been the lead singer of the Dropkick Murphys since 1998.
 He was also a founder and lead singer for The Bruisers, which he helped form in 1988 in Portsmouth, New Hampshire.
 His first band circa 1984, was called D.V.A. (Direct Vole Assault).
 He also went on to front 5 Balls of Power, with future members of Scissorfight, The Radicts, L.E.S. Stitches, and US Bombs, before he formed The Bruisers.
 His band the Bruisers had played many shows with Boston's Dropkick Murphys, and when Dropkick lead singer Mike McColgan quit the band in 1998 the Murphys asked Barr to be the new lead singer.
 The first album the Dropkick Murphys released with Barr as singer was 1999's "The Gang's All Here".
Rockaholic is the eighth studio album by American rock band Warrant, released on May 17, 2011.
 The album features the band's third lead singer, Robert Mason, who replaced original lead singer Jani Lane in 2008.
 Lane returned to the band for a 2008 reunion tour but by the end of the year, he and the band parted ways for the second time.
 Lane had previously replaced former lead singer Jaime St. James, who performed lead vocals on the band's last album, "Born Again", and who initially replaced Lane in 2004.
Adolf "Dado" Topić (born 4 September 1949, Siverić) is a rock musician from Croatia and the former Yugoslavia.
 He was the lead singer and founder of Time, a 1970s progressive rock band.
 From 1970 to late 1971, he was also the lead singer of the popular prog-rock band Korni Grupa (also known as The Kornelyans).
 He is a rock musician from Croatia and the former Yugoslavia.
 He was the lead singer and founder of Time, a 1970s progressive rock band.
 From 1970 to late 1971, he was also the lead singer of the popular prog-rock band Korni Grupa (also known as The Kornelyans).
 He is a male vocalist who sang the entry from Croatia in the Eurovision Song Contest 2007, together with the band Dragonfly.

Question: What city was the band Costadinos Contostavlos was lead singer for from?
Answer: London