As surprising as it may be, especially for this recovering metalhead, the Beatles are unshakably my favorite musical entity, be it Mozart to Metallica (a pair that shares far more in common than you might think) and beyond. 

I adore almost every damn thing the Beatles recorded (OK, I can skip “All Together Now”) and marvel endlessly at their unsurpassed songcraft, sappy lullabies to psychedelic loopings, to the point of becoming overwhelmed and misty-eyed. Their music moves me like a great Vermeer or Turner, an old Woody Allen or Chaplin flick, a sumptuous Bolognese, or a beautiful woman.

It’s nothing new, this affection. As a toddler, I was singing along to “Yellow Submarine” with my dad and having a ball (I have it on tape). But it’s been roused as I read Ian Leslie’s new book, “John & Paul: A Love Story in Songs,” a head-first spelunking into the two main Beatles’ musical/artistic/personal relationship as they composed some of their greatest tracks: “Yesterday,” “In My Life,” “Eleanor Rigby,” “Strawberry Fields Forever,” “A Day in the Life,” “Hey Jude.” It examines a plethora of terrific tunes, but places 43 under the microscope. Forty-three!     

Animated by fact and folklore, the book, which I admit I haven’t finished, begins in the beginning: how the boys met, formed early bands and honed their chops in German nightclubs. Yeah, yeah (She loves you, yeah, yeah) — that’s old news to Beatlemaniacs. It gets more interesting when John and Paul’s creative minds miraculously meld and songs start to pour forth in gorgeous, gobsmacking cataracts. 

The author launches with the somewhat green “Come Go with Me” in the late 1950s, strikes upon “Please Please Me,” with plenty of songs in between, and finally hits the stratosphere with “Ticket to Ride” and “We Can Work It Out.” It’s all joyride from there as the Beatles — George and Ringo included, of course, though they’re mere cameos — orbit Earth for seemingly ever. (But hardly. The Beatles lasted roughly 10 years, 1960-1970.)

Expectedly, Paul is painted as the pretty, peppy one, John the caustic, callous one. Yet both are endowed with bristling intelligence and an ample sense of play and worldly curiosity. They are autodidacts of the most ravenous kind, and they devour anything that has to do with art, literature and music. 

Their love of the American songbook, R&B and rock n’ roll is insatiable. And what they learn from them — doo-wop flourishes, country-western twang — dazzles. Their debt to Elvis and Dylan is bottomless.

The book is overstuffed with factoids, from the deep influence of Timothy Leary and LSD on the mid-career John song “Tomorrow Never Knows” to Paul asking George Martin for the kind of biting strings from the film “Psycho” for “Eleanor Rigby” — a masterpiece that Paul wrote at age 23.

It also doesn’t shunt on the group’s tour escapades, drug dabblings, interpersonal jealousies, and other gossipy gum drops. The book gleams with facets. Even at this early stage, Lennon and McCartney feel like brothers. My brothers. 

“John & Paul” is marvelous musicology, mind-blowing and wads of fun. It is my book of the summer, and I still have yet to reach “I Am the Walrus,” “Get Back,” “The Ballad of John and Yoko,” and, with terrible longing, yes, Paul’s heart-yanking “The End.”