Deep Purple songwriter Ian Gillan became the lead singer of 'Britain's biggest band' when he fronted a group of thousands of guitarists.
More than 3,000 people took part in Guitars on the Beach (GOTB), at Lyme Regis on Saturday.
Gillan decided to take part after hearing the organisers wanted to play Deep Purple's Smoke on the Water.
GOTB organiser Geoff Baker said the beach "erupted" when the Deep Purple vocalist performed.
He said: "You could have heard them roaring in Weymouth. It was like they were cheering the leader of their band. All of those 3,000 people were in the band."
Guitarists, from children as young as three to adults, came from across the country to take part in the event.
Before being joined by Gillan, 3,325 guitarists played the Status Quo hit Rocking all Over the World and Rave On by Buddy Holly.
The event set a new record for most guitarists playing simultaneously in Britain, breaking the record set by last year's inaugural event of 2,267.
Mr Baker said he would hold the event each year and wanted to break the world record of 6,546, which was set in Poland in 2009.
He said: "The whole town got involved. The local mackerel fishermen went out on their boats and when Ian Gillan played Smoke on the Water they released smoke grenades, so there was literally smoke on the water."
Mr Baker said the event raised between £6,000 and £7,000 for local charities.