Take That are to switch on central London's Regent Street Christmas lights later.
Thousands of people are expected to watch singers Gary Barlow, Howard Donald and Mark Owen turn on the lights at 17:00 GMT.
They are theme on the film Night At The Museum: Secret Of The Tomb.
The switch-on will be followed by fireworks and musical performances by Jessie J, Jessie Ware and The Jersey Boys.
In a statement, Take That said: "Turning on the Christmas lights in London is like the starter gun for the main event.
"It's the official start to the party season."
