As the movie opens, the Spice Girls are enjoying their fame, but becoming dissatisfied with the burdens of it. The sinister owner of a newspaper, Kevin McMaxford (Barry Humphries (also known as Dame Edna Everage)) is trying to ruin their reputation in order to cash in on the headlines, and even dispatches a photographer (Richard O'Brien) to take pictures and tape recordings of the girls. Less threatening but more annoying is a film director (Alan Cumming) who with his crew stalks the band, hoping to use them as documentary subjects; at the same time, the girls' manager, Clifford, (Richard E. Grant) is fending off two over-eager Hollywood writers (George Wendt and Mark McKinney) who relentlessly pitch absurd plot ideas for a Spice Girls feature film.
Throughout their busy schedule, the girls keep asking Clifford for time off to spend with Nicola (Naoko Mori),who is due to give birth soon, and to relax, but he refuses--mainly because his own boss, the cryptic and eccentric "Chief" (Roger Moore), won't allow it. The stress and overwork compound, culminating in a huge argument with Clifford and among the bandmates; the girls storm out, refusing to play Albert Hall.
Separately, the bandmates think back on their humble beginnings, their struggle to the top, and their strengthened friendship. They reconcile, then decide to take Nicola out dancing. However, she goes into labor at the nightclub and is rushed to the hospital in the tour bus. The band stay at the hospital to provide Nicola with support, refusing to perform until after she has given birth.
The next morning, the day of their Albert Hall gig, Nicola finally gives birth to a girl. As they are leaving the hospital, the girls bump into a doctor, but when Emma notices he has a camera, the girls realize the doctor is the photographer whose been stalking them in disguise. The photographer runs off with the girls in hot pursuit, only to hit his head on the wall after colliding with an empty stretcher, and when he sees the girls standing over him, he tells them that they've made him see the error of his ways, and he goes after the owner of the newspaper. After noticing their bus driver (Meat Loaf) missing, Victoria decides to drive herself. So, it becomes a race against time as she drives like a maniac to get to Albert Hall. The bus drives by Buckingham Palace, the the girls wave to the Royal Family, Victoria puts her foot down on the gas pedal when Tower Bridge starts to go up to let a boat through. They land safely on the other side, but when Emma opens a trapdoor in the floor, she discovers a bomb!
The girls finish the movie with a performance of "Spice Up Your Life".