London, Jan 26 : Pop star Britney Spears is doing mountains of research to make her gigs at London's O2 arena memorable.

The toxic hitmaker, who kicks off an eight-night residency on June 3, has been studying video footage of shows there.

She will also be sending aides to report back on upcoming gigs by Girls Aloud and the Pussycat Dolls.

"Britney knows these shows are absolutely crucial," the Sun quoted a source, as saying.

"She hasn't played in the UK for five years so there is a lot riding on them," the source added. (ANI)