Chris Martin, Lily Allen and Alesha Dixon are among celebrities urging volunteers to become "dementia friends" and help care for those with the degenerative condition.
Volunteers who take part in the scheme will be able to attend free sessions to learn how to spot the signs of dementia and offer support for sufferers, the Alzheimer's Society said.
In a new ad which will be aired for the first time tonight, the pop stars will be seen performing The Beatles' track I Get By With A Little Help From My Friends.
Other celebrities involved in the ad include comedian Simon Pegg, actor Ray Winstone, footballer Leighton Baines and presenter Paul O'Grady.
More top news
Aidan McAteer, 23, pleaded guilty via video link as Violet-Grace's mother wept in the public gallery.
The wife of a man who filmed himself killing their baby in Facebook videos, said she is not angry at the site or those who shared the posts.
Moyes told the BBC reporter she "might get a slap" following a post-match interview when Sunderland drew 0-0 with Burnley.