One Direction and stars from Downton Abbey and Strictly Come Dancing will be manning the phones in BT Tower tonight as part of the Typhoon Haiyan charity appeal.
The boyband will launch a special celebrity telethon via Twitter while a host of other stars will answer calls from people donating to the Disasters Emergency Committee's (DEC) emergency fund, which has so far raised £35 million for the humanitarian effort in the Philippines.
Broadcaster Andrew Marr, celebrity chef Jamie Oliver, comedian Stephen Merchant and actors Alan Rickman, Joanne Froggatt and Allen Leech also be answering calls at the iconic landmark in central London from 4pm to 7pm.
One Direction's Liam Payne said: "The pictures I have seen of little children in between the ruins made my heart break. All of us in the band are shocked by how many people need help, so we're asking the public to continue to be as generous as they possibly can."
Oliver said: "Families have been through the terrifying experience of the typhoon and now many face a daily struggle just to stay alive. I'm looking forward to answering the phones to the generous British public as we all do what we can to help."
Downton Abbey star Froggatt said: "This appeal is so desperately needed. I'm happy to be able to help. The more money the DEC raises, the more people they will be able to reach with vital, life-saving aid. The Filipino people urgently need our help to get back on their feet."
The £35 million raised by the DEC appeal follows a record £31 million being donated to Friday's annual Children in Need fundraiser which raises money for disadvantaged children and young adults in the UK.
Speaking on behalf of the 14 UK charities which make up the DEC, its chief executive Saleh Saeed said: "The kindness and generosity of the public has been overwhelming this weekend, a full week after the typhoon devastated parts of the Philippines, and the aid agencies represented by the DEC are extremely grateful for people's continued compassion.
"We are also grateful to so many celebrities who have given up their time to help out, and to BT who have been extraordinary in their support of the appeal to help raise even more funds. But more money is still needed for emergency aid and to help hundreds of thousands of people rebuild their lives."
You can donate to the appeal - and possibly have your call answered by a celebrity - by dialling 03706060610. Show your support on Twitter by using the hashtag #TyphoonAid.