Celebrities including singer Ellie Goulding, naturalist Chris Packham and actress Imelda Staunton have appeared in a video for Extinction Rebellion devised by Richard Curtis.
The short film outlines the demands of the group and asks governments what their plans are to tackle climate change.
It also features Jamie Winstone, Daisy Lowe, Jim Carter, Stephen Frears and Simon Amstell, as well as children from as young as eight as they demand a plan to address the crisis.
The concept for the film was developed by Love Actually director Curtis, and was shot and produced by Rankin, an agency headed up by the British photographer of the same name.
Goulding said: "We demand that we are involved in the decision making. It's our futures, too."
Packham said: "Time has run out. It's act now or face almost unimaginable consequences for life on Earth.
"So if the drivers of change are asleep at the wheel, it's time to shake and wake them with one hand and to empower ourselves to make our own differences with the other."
Winstone added: "This film must reach governments and ring the alarm bell to act now on the climate crisis we are all living in. We must all ask of them #WhereIsYourPlan."
