Watch: Elton John and Michael Caine in NHS ad for Covid jab
The 73-year-old I'm Still Standing singer is seen auditioning for the commercial, being asked by the director to be "a little less showbiz" as well as showing off a rather impressive Michael Caine impression.
Sir Elton tells the camera: "The more people in society that get vaccinated, the more chance there is of eradicating the national COVID pandemic.
"It is really important to know that the vaccines have all been through and met the necessary safety and quality standards."
The Rocket Man singer then overacts being jabbed in the arm before singing: "I'm still standing, yeah, yeah yeah!"
The director says they will let him know and Elton sneers: "Well, at this short notice you won't find anyone bigger."
The camera then cuts to 87-year-old actor Sir Michael, having an injection in his arm from a nurse.
He says: "Hello, my name is Michael Caine. I've just had a vaccine for COVID. It didn't hurt.
"Not many people know that."
Sir Michael – star of Alfie, the Dark Knight trilogy and numerous other films – has long been associated with the catchphrase "not many people know that", but it was actually the comedian Peter Sellers who coined the phrase in the 70s when doing an impersonation of the actor.
Both Sir Michael and Sir Elton have already had COVID jabs, which are currently being rolled out to everyone in the UK over 70, NHS frontline staff, vaccination centre volunteers, care home workers and residents, and others.
Over 12.5 million people in the UK have received their first dose of the vaccine and over 500,000 have had their second dose.
But some people are choosing not to take up the offer of having a jab, for reasons including fake news claims and conspiracy theories.
The government has set a target of vaccinating 15 million people by mid February, and chair of the vaccines taskforce Dr Clive Dix has said he is optimistic that everyone over 50 and all adults with underlying health conditions will have been offered a COVID vaccine by May.
The government has said it is "very concerned" about low uptake among black, Asian and minority ethnic communities.
Other celebrities who have already received jabs include naturalist and TV presenter Sir David Attenborough, 94, Bake Off stars Prue Leith and Mary Berry, 80 and 85 respectively, football manager Harry Redknapp, 73, singer Sir Tom Jones, 80. and actors Dame Judi Dench and Sir Ian McKellen, 86 and 81.
Katie Price's 18-year-old son Harvey, who has a range of complex needs putting him in the vulnerable category, and who lives at a residential care home, received his first dose last week.