Larry Hagman, who died of cancer Friday at 81, was a giant, and not just because the Stetson he wore in his most iconic role added a good six inches to an already long frame. J.R. Ewing is one of the all-time great TV villains, the defining character of the quintessential drama of the Greed Is Good 1980s.  

The character, and show, became so popular that more than half of all TV sets in America (and more than 3/4 of the sets that were on that night) were tuned in to the episode that resolved the legendary "Who Shot J.R.?" cliffhanger in the fall of 1980. The idea that viewers love to hate a villain never seemed more true than with J.R., who was nakedly driven by self-interest and yet so charming and funny and clever that you couldn't help rooting for him over his simpering good guy brother Bobby.

Even in his early 80s, playing a supporting role in a TNT "Dallas" sequel ostensibly focused on the next generation at Southfork, Hagman was still such a delight that his younger co-stars suffered terribly in comparison.

Hagman was a second-generation actor who got a few breaks thanks to his mother, Mary Martin. But he did far more with those breaks than most in his position ever have. As befuddled astronaut Tony Nelson on "I Dream of Jeannie," Hagman was the rare sitcom straight man who was genuinely funny in his own right. Though big roles were tough to come by in the decade after "Jeannie" — Hagman, like many sitcom stars before and since, was so identified with his famous role that many casting directors feared audiences wouldn't take him seriously as anything else — he did get supporting roles in movies like "Mother, Jugs & Speed" and "Harry and Tonto," and worked steadily as a guest star on other people's shows. 

Then came "Dallas." The show had been designed as a miniseries with Patrick Duffy's Bobby as the lead, in a Texas oil take on "Romeo and Juliet." But the show was popular enough to be turned into an ongoing series, and the center quickly shifted to the gravitational force that was Hagman as J.R. Though "Dallas" was rarely as campy as its primetime soap rivals like "Dynasty," Hagman often said that he approached the character as if he were still the lead in a comedy, and the dry pleasure he took in insulting Bobby, Linda Gray as wife Sue Ellen or the rest of the ensemble was infectious. Every season from 1980-1985, "Dallas" finished either first or second in the Nielsen ratings.

When news of Hagman's death came down late on Friday night, a Twitter follower asked if I could think of a good modern equivalent of Hagman, and there really isn't one. Other actors have had multiple hit TV series before, and some have even made the transition from comedy to drama. But Hagman's second act would be like if Bryan Cranston went from "Malcolm in the Middle" to "Breaking Bad" and "Breaking Bad" became the most popular show in the world for half a decade.

After J.R. was shot by a mysterious assailant at the end of the third season, Hagman realized that he had all the leverage with the studio and threatened to quit if he didn't get a raise to a then-enormous $100,000 per episode. Though producers reportedly considered either killing off J.R. or recasting him, everyone recognized that Hagman was "Dallas," and he got the raise.

Hagman drank heavily for much of his adult life, and got a liver transplant in 1995. A man who took his leisure seriously, at the height of his celebrity he would open up his home as the location of CBS' party at the Television Critics Association press tour. (This practice — which would never happen today — came to an end when, legend has it, Hagman caught an unscrupulous reporter going through his things in a room that had been declared off-limits.)

When the ratings for "Dallas" finally dipped into cancellation territory, the final season ended with J.R., in a low moment, appearing to commit suicide. But of course the character was too beloved to die; in a reunion movie five years later, it was revealed that J.R. shot a mirror, and not himself. (As "Dallas" resurrections went, it was better than Bobby stepping out of the shower and revealing an entire season as a dream.)

Hagman was an enormous star, but he was also a superb actor, as he was able to demonstrate now and then in his post-"Dallas" years. In Mike Nichols' "Primary Colors," Hagman walked away with the movie as a straight-talking former Florida governor trying to hide a cocaine addiction and all the indiscretions it caused. ("Hell, I could handle anything," he says ruefully, "exception cocaine. Only I didn't know that because of cocaine.") He did memorable guest stints on "Nip/Tuck" and "Desperate Housewives," and even as he battled the cancer that killed him, he owned every frame of the new "Dallas." He had filmed a reported six episodes of the TNT show's second season, and the producers will attempt to continue without him. But it's hard to see the point in that beyond keeping the cast and crew employed. The new "Dallas" isn't remotely as popular as the old one, but whatever juice it had came from the crafty old man with the sculpted eyebrows and big white Stetson. Now he's gone, and with him all of the fun down at Southfork.

(The Austin Film Society recently put together a highlight reel of Hagman's career, including that great moment in "Primary Colors.")

Alan Sepinwall may be reached at sepinwall@hitfix.com