Wyatt Earp, if you didn’t know. I’m old enough to have watched the series when originally telecast.
He had plenty of other TV credits; he was on Fantasy Island 5 times as 5 different characters, and Police Story 3 times.
I had not known he was still alive. COZI TV runs Wyatt Earp regularly, so I’ve seen pretty much every episode. I shall raise a glass of milk in his memory. Long live his fame and long live his glory, and long may his story be told.
I’ve never seen his earlier stuff; to me, he was just the answer to the question, hey, who was that old guy who was so incredibly fit that, for the plot to work, everyone accepts within seconds that he’s Schwarzenegger’s long-lost dad in Twins? Huh. USMC in the '40s, action hero in the '50s? Yeah, that makes sense. I mean, just look at him.
I was surprised he was still alive, thought he died years ago. I remember watching the old Wyatt Earp show is the days of Westerns on TV.
Look at his IMDb page shows he played Wyatt Earp an amazing number of times. As late as 1994 when he was almost 70. (Checking I see the reap Wyatt Earp lived to 80.)
His last role was in 2000. But there’s a WWII Vet movie with him, Rance Howard, and Clifton James in pre-production. So that’s a problem there.
Loved his bit in Twins.
One of those times was in the pilot movie for Fantasy Island.
I loved SEARCH!, 1972–73. Star Trek without the Enterprise!
Me too. “Brave, courageous and bold. . .”
Trivia: O’Brian was the last person ever killed by John Wayne in a movie, in The Shootist.
He created a service organization called HOBY that taught leadership to teenagers, after he and Norman Cousins spent several days doing volunteer work with Albert Schweitzer in Africa back in 1958 (how’s that for rubbing elbows!?). Nearly half a million kids have been through it.
It also sounds like he banged a legendary number of women. 
You may have confused Hugh O’Brian with Cliff Robertson, who died in 2011. (But not Mitchell Ryan - he’s still alive.)
Sad to hear, I was one of the HOBY kids. When it first started, he brought one high school sophomore (promising science students) from each state and some of the territories to Cape Canaveral for a week. I was the RI rep in 1972. We stayed in Air Force barracks on the Cape.
Got to go all over the space center (including up inside the top of the VAB), watch a hypergolic fuel demo, meet the coach of the Washington Redskins, and meet with Hugh O’Brian himself at one point. Coolest was talking to astronaut Dave Scott and passing around one of his boots that had walked on the moon.
Was cleaning out the basement recently and found my red HOBY windbreaker that I was given. To quote Disney’s Country Bears Jamboree “still fits, sorta”.
The dude was HOT back in the day! He did get married finally, to his long time companion, when he was eighty-one.