Many actors play superheroes, but few have a unique and iconic hold on their characters in the popular imagination. (Marvel Studios)

AS “DEADPOOL 2” officially opens Friday, cutting a swath of three-dimensional violence and broken-fourth-wall humor, the motor-mouthed Ryan Reynolds reminds us why this is the superhero he was born to play.

In an era when many big-screen superheroes seem interchangeable — we’ve had three Spider-Men, three Hulks and four Batmen (five if you count the “Lego” movies) in the past quarter-century alone — there is something impressive about an actor who is able to make a costumed role utterly his or her own. When a performer becomes the definitive portrayer of a comic-book character, even fickle fans and recast-happy Hollywood tend to respect this fortunate fusion.

Among current cinematic superheroes, here are the crime fighters who have become most inseparable from the actors who inhabit them.

Chris Hemsworth takes up the hammer again in “Thor: Ragnarok.” (Jasin Boland/Walt Disney Pictures)

5. THOR / Chris Hemsworth:

Among the Marvel Cinematic Universe’s Avengers, the mantle of Black Panther may eventually pass from T’Challa (Chadwick Boseman) to Shuri (Letitia Wright). Similarly, the Captain America shield could readily be handed from Steve Rogers (Chris Evans) to Bucky Barnes (Sebastian Stan).

Yet while Thor may be a malleable property in the comic books — exemplified by the decision to have Jane Foster pick up the hammer — Hemsworth has carved out an iconic embodiment of the silver-screen Asgardian, particularly in the past year with the comedic “Thor: Ragnarok” and “Avengers: Infinity War.”

You can chop his locks, but Hemsworth should rightly have years before a permanent transfer of his hammer is considered.

Gal Gadot takes up her own sword for “Wonder Woman.” (Warner Bros./DC 2017)

4. WONDER WOMAN / Gal Gadot:

The shadow of TV’s “Wonder Woman” was so long — thanks to Lynda Carter’s classy inhabiting of the role in the ’70s — that finding the right actress for the big-screen incarnation was still a real challenge four decades later. For generations of fans, who could measure up to Lynda?

But that was before Patty Jenkins directed Gal Gadot in last year’s smash “Wonder Woman.”

Zack Snyder helped bring the model turned “Fast and Furious” franchise actress into the DC fold, and although Gadot was minimally used in his “Batman v Superman: Dawn of Justice” — and criminally underwritten in the “Justice League” movie that he launched — the casting of Gadot paid off perfectly once the actress’s Diana Prince got a shot at going solo.

Gadot burned brilliant in Jenkins’s spotlight — mostly free of DC’s signature sludgy darkness and erratic pacing — and the former real-life warrior proved winningly adept at both comedy and combat.

The re-teaming of Gadot and Jenkins for the sequel should only cement her hold on the role.

Wolverine (Hugh Jackman), perhaps at the end of his run, watches over multiple generations in “Logan.” (Twentieth Century Fox 2017)

3. WOLVERINE / Hugh Jackman:

There’s no way even director Bryan Singer could have foreseen, when auditioning an “Oklahoma!”-acting Aussie unknown nearly two decades ago, just how fused Hugh Jackman would become with his “X-Men” role as Wolverine.

Jackman was a foot taller than the comic-book creation of Wolverine/Logan, and he little resembled the overall look of the brightly costumed Wolverine, save for bushy sideburns and a stogie. Yet Jackman’s charisma and feral ferocity quickly won over the filmmaker — and kept fans turning out for even the lesser X-films (with 2009’s “X-Men Origins: Wolverine” being a particular disappointment).

Last year’s Oscar-nominated “Logan” was a spectacular high point, and if that film remains Jackman’s swan song as Wolverine (with his mutant daughter inheriting her own mantle), then may filmmakers let the X-role rest respectfully in peace.

Robert Downey Jr.’s Tony Stark, center, again leads the way — with assistant Happy Hogan (Jon Favreau), left, and Peter Parker (Tom Holland) — in “Spider-Man: Homecoming.” (Sony/Marvel Studios)

2. IRON MAN / Robert Downey Jr.:

It was a lasting stroke of career-resuscitating genius when director Jon Favreau cast Robert Downey Jr. — the whipsmart Oscar-nominated talent whose career had been derailed by addiction and prison — to play Iron Man/Tony Stark, the genius playboy mogul who battled his demons of the bottle.

Downey Jr.’s gift for fast patter, electric chemistry and wounded-man portrayals not only made 2008’s “Iron Man” a surprise hit, but his talents, including the ability to play very well with other Avengers, also launched the Marvel Cinematic Universe.

Downey Jr. may be counting his remaining MCU years as much as his monster Marvel receipts. But there’s really no replacing his kinetic core energy that has helped power a decade of movies (with the second “Infinity War” film still due next summer).

Ryan Reynolds returns in “Deadpool 2.” (Twentieth Century Fox)

1. DEADPOOL / Ryan Reynolds:

It’s not just that Ryan Reynolds portrays the Merc With a Mouth so seamlessly, no matter how uncomfortable that oft-bullet-pocked crimson suit becomes. The degree to which the comic actor and comic-book character are inseparable is reflected in Reynolds’s utter commitment to these Fox projects.

Reynolds and his buddies willed this character to the screen — including with strategic footage leaks — after “X-Men Origins: Wolverine” unveiled a mute take on Deadpool that stands as one of the biggest blunders in superhero cinema.

After his “Green Lantern” bombed, Reynolds grew all the more dedicated to getting his version of Deadpool on the screen, even contributing crucially to the writing.

As “Deadpool 2” prepares to see its domestic debut top $150 million, according to industry projections, Reynolds and the katana-wielding Wade Wilson remain joined at the hip — and should do so as long as the character is even semi-hip.

Read more:

From ‘Avengers: Infinity War’ to ‘Iron Man’: All 19 Marvel Cinematic Universe movies, ranked

Review: ‘Deadpool 2’ does not care about your feelings. That’s what makes it work.