For most people who know of Auberjonois, a prolific and talented actor who has just died at age 79, he's probably mostly famous for his TV roles. But for me, Auberjonois was the first person I ever saw play Edgar in KING LEAR, and every time I saw him afterwards, I always thought back to his performance in that role, in the Joseph Papp-produced version that aired on PBS in Houston (and elsewhere) in 1974. He was excellent and held his own against James Earl Jones (Lear) and Raul Julia (Edmund). Rosalind Cash, whom I had known only from the schlocky Charlton Heston movie THE OMEGA MAN, was a compelling Goneril. Auberjonois's Edgar and Paul Sorvino's Gloucester in many ways stuck in my memory even more than Jones's Lear or Julia's Edmund did. For one thing, it's easier to figure out things about Lear and Edmund and Goneril just from reading the characters on the page, but I didn't understand how someone could be Edgar or Gloucester until I saw Auberjonois and Sorvino play those roles. For another, the play as a whole turned a switch in my mind and made me think, abruptly, that I could perform Shakespeare roles myself and make the language and the characters come alive. I didn't have any plans in high school ever to perform Shakespeare--I had performed in high-school theater of the musical-comedy variety mostly, but it wasn't a career thing--but this TV performance of LEAR seeded in me the desire to perform Shakespeare someday if I ever got a chance.

Doc and Shakespeare at Winedale (which I hadn't yet heard of in 1974) gave me that chance. And Auberjonois had showed me how it was possible to perform a classic role and demonstrate things about about a character that one couldn't necessarily see in just reading in the lines. 

René Auberjonois, 'Star Trek' and 'Benson' Actor, Dies at 79  

https://www.hollywoodreporter.com/news/ren-auberjonois-dead-star-trek-benson-actor-dies-at-79-1260677 via @thr

Here's the IMDb listing for the "Great Performances" installment that aired Papp's LEAR. 

I've also attached a pic.