And the performance, a 20-minute taster of the touring production of Let It Be, which features 40 of the Beatles' greatest hits, was probably more slick than the Fab Four were themselves.
Reuven Gershon, James Fox, Stephen Hill and Luke Roberts play John, Paul, George and Ringo. And they hit the right note every time, from their stage presentation to their tight harmonies.
"We work really hard on getting it right," says Cardiff-born James, who appeared on the BBC's Fame Academy and starred on Broadway in the Billy Joel musical, Movin' Out.
"And when you think that we play for two and a half hours, and the Beatles did sets of just 20 minutes, you realise we have to get it right."
Reuven, who has played John Lennon on stage and screen several times, agrees. "It's about the sound, but there's also performance required. You have to get the mannerisms, the accents right."
Stephen Hill has played George Harrison in Beatles' tribute bands for years.
"It's about becoming George," he says. "Getting every note, every movement."*
l Let It Be, the King's Theatre, April 28-May 3. Tel: 844 871 7627.