Van Sant has long pursued a dual career as a Hollywood filmmaker (from “Good Will Hunting” to “Milk”) and also as a director of youth-culture indies, beginning with seminal late-’80s/early-’90s films like “Drugstore Cowboy” and “My Own Private Idaho.” He no longer has much of an American audience in the latter category; roughly since “Gerry” and “Elephant” (which won the Palme d’Or here in 2003) he’s belonged to the Woody Allen-Jim Jarmusch club, as an auteur celebrated in Europe but ignored at home. “Restless” feels like an attempt to split the difference between the mass-market success of “Milk” and the near-total invisibility of, say, “Paranoid Park,” Van Sant’s moody 2007 exploration of Portland skater culture. That’s not a terrible idea, and remaking “Love Story” for the “Twilight” generation probably isn’t a bad idea either, but you never quite feel that this mild, eccentric sub-”Harold and Maude” vision of death engages Van Sant’s full attention.

Looking strikingly like her namesake Mia Farrow, with close-cropped hair and a boyish wardrobe, Wasikowska finds a specific energy in Jason Lew’s rather bland screenplay, making it clear that Annabel’s relentlessly sunny demeanor is driven by a steely ferocity. She’s going to die and she knows it, but she won’t give in to the rhetoric of death, and insists on viewing it from a detached perspective. She’s fascinated by Darwin and memorizes details about seabirds and insects, as if trying to put the impending end of her short life into a greater evolutionary perspective. As she tells her protective older sister Lizzie (Schuyler Fisk), viewed in geological terms dying in three months is no different from dying in three days or 30 years. When she spots Enoch (Henry Hopper) at a friend’s funeral, she ID’s him immediately as a chronic funeral-crasher — he’s dressed too formally, and his manner is too downcast. “No one wears black at these things anymore,” she says. “It’s a bummer.”

Hopper looks at first glance — and second, and third — startlingly like a boyish, blond version of his late father, Dennis Hopper, and it’s hard to say whether that helps or hurts the film. The younger Hopper doesn’t have his dad’s natural ferocity as an actor, but neither does anybody else. He isn’t terrible by any means, but this is his first adult movie role (he’s 20) and Enoch is a maddening character who reveals almost nothing about himself but is expected to carry much of the film’s emotional weight at critical moments. At first he wants nothing to do with Annabel; it’s almost like she’s decided she wants a boyfriend for her last weeks of life, and even this deranged loser will do. His parents are dead; he goes to funerals but not to school; his best (and only) friend is the ghost of a World War II kamikaze pilot (Ryo Kase). When he’s not at funerals, he sits in his room playing Battleship with his spectral Japanese pal, and losing.

There’s no denying that these two look great together — Hopper certainly has the bored, androgynous beauty Van Sant has always admired in his leading men — and I’d say that the director and his stars come close to rescuing “Restless” from the pileup of whimsical details and the relentless jangling of the indie-pop soundtrack, which ruins almost every intimate moment. There’s a misty, lovely Halloween interlude (the second such scene I’ve seen in two days — has every director been studying the Blu-ray of “Meet Me in St. Louis”?) that finally brings this chaste duo together as lovers and reminds us that they’re not much more than damaged children, trying to face a tragic twist of fate on their own terms. You can’t come away totally hating “Restless,” especially since Annabel and Enoch may well be right that life and death and love are transitory phenomena, not to be taken too seriously. But in that case movies don’t matter either, and the chronically diffident Gus Van Sant is not the guy to argue otherwise.

Humans are pattern-seeking creatures. We’re the species that can find Jesus’ face in a frying pan and cite the cover of “Abbey Road” as proof that Paul is dead. But when you really want to prove the uncoincidental nature of the universe, three is the magic number. Three has a certain music to it. It works, rhythmically. Its origins are shrouded in the mists of time — the idea that deaths come in threes predates celebrity — but high-profile deaths certainly gave the theory a boost.

In truth, the only authenticated incident of celebrity death occurring in triplicate was Feb. 3, 1959, when Buddy Holly, Ritchie Valens and the Big Bopper went down together in an Iowa plane crash. But we’ve been looking for approximations ever since, with occasionally persuasive results.

Isn’t it weird that Johnny Cash, Warren Zevon and John Ritter all died in the same September week in 2003? Or that Suzanne Pleshette, Brad Renfro and Heath Ledger all shuffled off the mortal coil within a seven-day period in January of 2008? And when Michael Jackson and Farrah Fawcett died last June 25, just two days after Ed McMahon finally joined Carson on the other side, that couldn’t have just been random, could it?

Note the elegant symmetry there. For the rules of celebrity death clusters to work, the stars should be of similar magnitude, and the deaths should come within a close time span. Hence, OxiClean pitchman Billy Mays’ death last June 28 doesn’t make for a rare quartet because he wasn’t famous enough, and David Carradine’s passing on June 3 is disqualified because it was too early in the month. And while trend spotters may wonder how Jimi Hendrix and Janis Joplin managed to die in the same month in 1970, or Princess Diana and Mother Teresa expired in the same week in 1997, two of anything is still officially just a coincidence.

The axiom isn’t just handy for celebrities either. “Death comes in threes” is a persistent superstition even in families and communities where nobody’s ever been the subject of an E! True Hollywood Story. And the notion that catastrophes and fads arrive in waves of three is the basis for 50 percent of all the stories in the New York Times’ Style section.

Which brings us to Hopper and Coleman, the countless celebrity lives that no doubt remain in jeopardy, and the online speculation that will continue until the next famous person leaves behind this vale of tears. Though the two men’s statures were far from equal, their quirkiness, their willingness to appear in some real schlock, and most of all, the proximity of their deaths unites them forever, begging for a third to complete the circle. You’d have thought the gods already proved their point when Lynn Redgrave, Ernie Harwell and Lena Horne died within days of each other earlier in month, but obviously no.

One could note that there are a lot of people in the world who’ve attained some degree of notoriety in their lives, many of whom are old, sick, fly in airplanes, have a more than recreational relationship with the pharmaceutical industry, or are otherwise subject to the laws of mortality. One could further say that Alexander McQueen, J.D. Salinger and Corey Haim made it to Boot Hill this year without setting off any copycat epidemics. But where’s the fun in that?

Death, that great, random and cruel mystery, will have dominion over all of us yet. All we can do in the meantime is pretend to understand it — with steadfast magical thinking, lighthearted wagering, or a little bit of both. Not because we’re primitive or callous. But because sometimes when we lose people, especially people who made movies we love or TV shows that remind us of childhood or music we rocked out to our in our bedrooms, the need to believe in something is compelling and comforting. It imposes sense upon the senseless. So if it helps, I say that metal god Ronnie James Dio, who died the week prior to Coleman and Hopper, is a completely valid candidate for the trio. Consider fate appeased. And Larry King safe.

Hopper appeared in a handful of memorable films — “Apocalypse Now,” “The American Friend” and “Blue Velvet,” along with his own “Easy Rider” — and a seemingly infinite litany of forgettable ones. Even when he performed in children’s TV or straight-to-video Eurothrillers or the 1993 film version of “Super Mario Bros.,” you always had the feeling that Hopper was performing a kind of existential high-wire act, perhaps more for himself than the audience: How much of his own soulful madness would he let out? How much of the inanity and mediocrity around him would he absorb?

On the one occasion when I met Hopper, at a film-festival party in San Francisco about 15 years ago, he gave a vintage performance, drinking wine and laughing it up with a group of people he barely knew (or, in my case, didn’t know at all). He wore a white linen suit and a trim goatee, regaled us with yarns from his heyday as a “total madman” in the 1960s, and looked terrific against what I remember as a crisp, sunny day. At some point his female companion — I’m not going to try to figure out who that was, and it doesn’t matter — stalked off after some heated private conversation, but he didn’t seem concerned.

When I asked Hopper what he remembered most about James Dean, with whom he appeared in “Rebel Without a Cause” and “Giant,” his demeanor changed. He became intensely earnest, explaining that Dean had changed his approach to acting and to life. Hopper had begun acting in television at a time when it was all about clarity and economy, he explained: You hit your mark, you said your lines clearly, you made your exit. Then he got on the set of “Rebel Without a Cause” (his film debut) and met Dean, who had been studying under Lee Strasberg at the Actors’ Studio in New York.

“Here was this kid, Jimmy — I mean, he was older than me, but he was still a kid,” Hopper said, “and the stuff he was doing was amazing, it just blew me away.” (I won’t pretend these are verbatim quotes; this is the conversation as I recall it.) He remembered Dean rolling around on the carpet of the set that was supposed to be the Stark family’s Los Angeles home. “I asked him what the hell he was doing. I mean, you just didn’t do that. It was completely from another planet.” Dean explained that Jim Stark, his alienated teenage character, had spent a lot of time on that carpet and was intimately familiar with it. He needed to know what it felt like.

Along with Marlon Brando, Dean was one of the principal vectors for the transmission of Strasberg’s “Method acting” approach into the Hollywood mainstream, and Hopper became an eager disciple. (Publicity photographs from “Rebel Without a Cause” show Hopper reading Stanislavski’s “An Actor Prepares” on the set, which can only have been Dean’s idea.) After Dean’s death, Hopper abandoned Hollywood for Manhattan and spent five years studying under Strasberg. In later years, as the Method came to dominate American film acting, several of its practitioners became much bigger stars than Hopper: Robert De Niro, Al Pacino and Sean Penn, along with Hopper’s close friend Jack Nicholson. But I’m not sure any of those men internalized the Method, or pursued its philosophical and psychological dimensions to their logical extremes, the way Hopper did.

Viewed narrowly, the Stanislavski-Strasberg Method is a means to an end: An actor employs his own emotions, memories and sensations in order to portray a character in more lifelike and convincing fashion. Hopper seemed to develop his own expanded, synthetic interpretation, probably shaped by his appetite for consciousness-altering substances, avant-garde art and thorny philosophy. Every Hopper performance was just a facet of his lifelong, overarching performance as Dennis Hopper, and the professional separation most actors maintain between themselves and their characters evaporated entirely. Apocryphal or not, the story of Hopper’s phone call to David Lynch after he had read the script for “Blue Velvet” is on point: “You have to let me play Frank Booth. Because I am Frank Booth!”

Of course Hopper wasn’t really an amyl-nitrite-huffing, psychopathic rapist any more than he was a disgraced Indiana basketball coach (as in “Hoosiers”) or a disgruntled bomb-squad officer (as in “Speed”). But he pursued roles as dangerous and damaged characters, at least in the second half of his career, with a fervor that suggests he found them personally therapeutic as well as financially rewarding. Frank Booth was a revelation because he was horrifyingly, recognizably real, in a way movie villains hardly ever are. Even with his exaggerated vices and mannerisms, his foulness was rooted in genuine pain. (And Frank’s profane preference for Pabst Blue Ribbon over Heineken launched a trend among young consumers that endures two decades later; the brewery should have paid Hopper and Lynch a lifetime commission.)

Right after his breakthrough 1986 performance in “Blue Velvet,” Hopper starred in the hoops drama “Hoosiers,” a commercial success which garnered him, amazingly enough, the only Oscar nomination of his entire acting career. (He had been nominated for best original screenplay for “Easy Rider,” along with co-writers Peter Fonda and Terry Southern.) After that, he returned to the director’s chair for the first time in 17 years, making the solid L.A. gangland drama “Colors,” a midsize hit. A late-career renaissance as a star character actor and indie auteur beckoned, but Hopper, in entirely typical fashion, just didn’t seem to care about that, or even to think about himself in conventional, careerist terms.

He spent the last 20-plus years, in fact, doing about the same stuff he did for the 20-plus years before that: Acting feverishly, in whatever context presented itself. You’ve seen or heard Hopper in big, noisy movies (“Speed,” “Boiling Point”), smaller, quieter ones (“Red Rock West,” “Jesus’ Son”), TV series (“24,” “E-Ring,” “Crash”) and a baffling array of video games, documentaries, animated specials and indistinguishable direct-to-video crime films. (Have you seen “Lured Innocence”? “Bad City Blues”? “The Spreading Ground”? If so, I salute your devotion. Now, please get professional help.)

From a normative, celebrity-centric point of view, Hopper’s career has been a series of failures. He failed to cash in on his early acclaim as Dean’s co-star with major movie roles, failed to turn his anarchic, lightning-in-a-bottle success with “Easy Rider” into a directing career, and failed to turn his post-”Apocalypse Now” comeback into anything approaching the brandy-snifter, lion-in-winter act we expect from aging actors. But each of those failures stemmed from the one before it, and Hopper used each one to create the Zen bon-vivant persona that was fed by all those deranged guys he played on screen but was bigger and more satisfying than any of them.

At some point in the late ’50s or early ’60s, Hopper must have realized that a guy with an aquiline face, ferocious eyes and the body language of a rabid terrier wasn’t going to become a movie star. So he made a living on TV and became an important portrait photographer, as well as an autodidact art collector who helped introduce modernist and postmodern art to Los Angeles. He used his Hollywood outsider status as creative fuel in making “Easy Rider” with Fonda, Southern and Nicholson. In all its post-adolescent male angst and self-centered artistic ambition — director Henry Jaglom was called in to edit Hopper’s 220-minute version into something releasable — is an awkward mishmash of a movie, but an enormous cultural milestone.

In an era when virtually every Hollywood actor and director ingested all sorts of elaborate chemicals, Hopper became the media’s whipping boy for drug abuse. After the critical and commercial debacle of “The Last Movie,” his semi-experimental follow-up to “Easy Rider,” his directing career lay in ruins and he evidently decided to live the part fully. But the idea that Hopper’s ensuing European exile was nothing but lost years of cocaine and crap movies is at least partly undermined by the evidence, most notably his terrifying turn as Patricia Highsmith antihero Tom Ripley in Wim Wenders’ brilliant “American Friend” (for my money, the second-best Hopper performance of all, after “Blue Velvet”).

Hopper clambered back into the American limelight with “Apocalypse Now” and got partly and conditionally sober in the early ’80s and moved on to play Frank Booth and Frank Sinatra (in an Australian film I’ve never seen) and supervillain Victor Drazen in “24″ and whoever he played in an animated special called “Santabear’s High Flying Adventure.” He eventually got old and sick and now he is dead, leaving behind one of the strangest peaks-and-valleys legacies in showbiz history. I think the whole time he was rolling around on the carpet. In order to be Dennis Hopper from one moment to the next, he needed to know what it felt like.