Mutya Keisha Siobhan Explores Los Angeles in 'Flatline' Video: Watch

An ordinary day in Los Angeles turns into an unexpected marching band jamboree for Mutya Keisha Siobhan in the music video for their great new single "Flatline," which was released on Sunday (Aug. 18). The former Sugababes will release their first official single under the MKS name through digital retailers in the U.K. on Sept. 15.

Filmed in L.A. last month, the "Flatline" clip finds Mutya Buena, Keisha Buchanan and Siobhan Donaghy playing on bicycles, under palm trees, alongside skateboarders and on a sparkling beach before deciding to high-tail it to the valley in an orange convertible. Once there, the ladies run into a full marching band, who add some choreographed punch to the soaring bridge of the single. 

Mutya Keisha Siobhan Returns: Inside The Original Sugababes' Comeback

"Flatline," which was written and record in L.A. last February with producer Dev Hynes, previews MKS' first album as a trio since the Sugababes' 2000 effort "One Touch," after which Donaghy departed the group. By 2009, all three U.K. singers had deserted the girl group, and after reconnecting soon after, Mutya Keisha Siobhan signed to Polydor Records in 2012.

"There's no plans just yet," Buchanan told Billboard last month regarding a U.S. release of MKS' album, "but this is the most response … that we've ever had stateside, so you never know. We're gonna push for it."