"My dad just sits around all day playing the piano," he would answer.

His dad, legendary music producer George Martin, always made it look easy. And yet over the past four years, as father and son labored together to remaster and remix original Beatles tapes for a new Cirque du Soleil production called Love opening June 30 in Las Vegas, Giles is finding out just how talented his old man was.

The world will focus on Love as a lavish revisiting of one of the most storied chapters in pop-culture history. And the paparazzi will be in rapt attention when Paul McCartney and Ringo Starr, and the widows of John Lennon and George Harrison (Yoko Ono and Olivia Harrison), gather for a gala opening at the Mirage Hotel-Casino.

For the Martin men, it's a quieter tale of an 80-year-old father suffering from hearing loss who has anointed his son, 36, as the new defender of one of pop music's most important canons.

When George Martin came out of retirement to create a soundtrack for the $150 million production, he knew he'd have to ask for a helping hand.

"He's my natural selection for someone to work with because I trust him implicitly, and he's a very good musician," he says, looking across the couch of his Mirage suite at his son, who has the same lanky build and broad, cheek-rippling grin. "And he happens to be a guy I love very much."

The 90-minute show they've scored offers a loose retelling of The Beatles' story, opening with Get Back, from the band's final concert on the Savile Row rooftops of Liverpool, England. The action rewinds to bombed-out Liverpool in World War II, when the future Fab Four were born, to the tunes of Glass Onion and Eleanor Rigby.

All along, dancers and acrobats perform, bouncing from literal interpretations to fairly obtuse references. About 25 full songs are in the show, and more than 100 others are represented in ways often unnoticeable to the unschooled. (An opening guitar riff, for instance, is all that's used from A Hard Day's Night.)

George Martin signed the foursome in 1962 and molded them into the century's biggest-selling band. He went on to produce acts as varied as Kenny Rogers, INXS and Celine Dion. He's now likely among the few octogenarian fans of Franz Ferdinand, Coldplay and Radiohead.

Giles, his last of four children from two marriages, arrived at the end of the Beatles decade, born on John Lennon's birthday in 1969. He's not even sure he ever met Lennon, who was killed in 1980.

"We weren't surrounded in a Beatles world coming up," says Giles, noting that his family didn't even have a hi-fi stereo in their living room. "We didn't sit around and say, 'Let's put on the Yellow Submarine.' When I was a kid, The Beatles weren't a band everyone was talking about."

George tried to dissuade his son from a musical career, fearful his son would be compared with his own success. Giles began showing promise in his teens, but his record-producing dad did nothing to help him land a record contract for his band, Velvet Jones.

"They weren't good enough," George grins. "I'm a producer. I have a job to do. You've got to be really, really good to make it. "

Giles became a songwriter and producer anyway. His successes include producing for the British psychedelic rock band Kula Shaker and 2004's Pure, one of the UK's fastest-selling classical albums.

The Cirque and Beatles folks rave that having Giles around is like having a younger version of George, but his role in Love is controversial among Beatles purists.

Giles has digitized Beatles tapes and remixed them, making such radical changes as placing the drum track from Tomorrow Never Knows on Within You Without You. George says he wishes he had thought of that for the originals.

"We would never do anything that I think is alien to The Beatles," George says. "To me, everything that has been done is available anyway. If the people don't like (this), they can stay with the stuff that's already there. It's not the Holy Grail. If anyone has the right to do this, then I have."

But Giles isn't entirely sure such a right is transferable. He rejects the notion that a legacy has been passed on to him, but he does see himself in Love as an emissary bringing The Beatles to new generations. And he feels that through the project, he has come to understand his father's life.