Diane Keaton was an irreplaceable supernova of smarts, charm and boundless energy

If there’s one quality that defined Diane Keaton’s five decades of peerless movie performances, it was her irrepressible and unpredictable energy. 

That’s what made the news of the Oscar winner’s death on Saturday at age 79 such a devastating shock. 

All the way through to 2023’s “Book Club: The Next Chapter” and 2024’s “Summer Camp,” the actress was still the same galvanic woman who played Annie Hall, Kay Adams-Corleone and Erica from “Something’s Gotta Give.”

Her passion, smarts and force of personality were remarkably never dulled by time, arresting the big screen in memorable role after memorable role, right to the end. 

Born in Los Angeles and trained in New York, every turn of Keaton’s had both the laid-back vibe of an afternoon on Santa Monica Beach and the volcanic stress of a Manhattan subway commute in equal measure.

When she was happy, we felt pure euphoria. When she snapped, everybody watch out.

Vitally, Keaton had a natural presence that commanded respect — from us, her fellow actors and any poor character than dare challenge her.

Keaton already had seemingly accumulated 79 years of pathos and wisdom by 26 when she appeared in the 1972 film “Play It Again, Sam,” which she previously starred in on Broadway, beginning a long and fruitful collaboration with Woody Allen.

She quickly went on to be a key player and iconic face of Hollywood during the 1970s, arguably the greatest decade in film history. 

What was so blissfully unique about her was the way the actress was, at the same time, a free spirit and an upright authority figure; a font of intellect, wit and charm who was a scream when she’d finally let loose. That exciting tug of war so brilliantly balanced out her director and co-star Allen’s joy-averse, off-the-charts neuroses. 

The image of Keaton in 1977’s “Annie Hall” decked out in a black vest with a necktie and a bowler hat — a signature look in real life, too — is cemented in movie lovers’ minds. So is her genuine and beaming smile. It’s one the the all-time great performances.

Her sneaky danger was perfect for Kay in “The Godfather” trilogy. Believe it or not, Francis Ford Coppola’s original was just her third movie. At 28, Keaton had such a gentle exterior in “Part II,” and then dropped the “our marriage is an abortion!” speech to Al Pacino’s Michael like a Cosa Nostra nuke.

As with Allen, the actress ideally countered Jack Nicholson’s Casanova who likes ‘em young in 2003’s “Something’s Gotta Give.” And she was the most grounded member of 1996’s “The First Wives Club,” opposite loonier Bette Midler and Goldie Hawn, even as her character Annie’s outwardly gorgeous life movingly crumbled to pieces.

Later in her career, Keaton lifted lighter fare with her enormous talent. “The Family Stone” has turned into a Christmas tradition for many. And, while the “Book Club” series isn’t top-drawer stuff, she’s her usual brilliant self in them.

Everybody loves the end of “First Wives Club,” when Keaton, Midler and Hawn sing the Leslie Gore song “You Don’t Own Me.”

The defiant lyrics sum up the much-missed, forever formidable, irreplaceable actress terribly well.

“You don’t own me. Don’t try to change me in any way. You don’t own me. Don’t tie me down ‘cause I’ll never stay.”