Ruben Santiago-Hudson is a celebrated Broadway director, producer, playwright and actor, also possibly the world’s leading proponent for playwright August Wilson, who died in 2005.

Then — almost as an afterthought — there’s TV.

Santiago-Hudson, 61, has starred on “Billions” the past few seasons, and on the ABC hit “Castle” during most of its run. Over the decades he’s typically played the thoughtful, sober type — judge/doctor/cop — so his latest series, the excellent OWN newcomer, “David Makes Man” (Wednesdays at 10 p.m.) feels custom-fit: As the wise Dr. Bree, he attempts to unravel the psychic mysteries of David (Akili McDowell), a gifted kid in the Florida projects who conducts animated conversations with a dead drug-dealer (“Hamilton’s” Isaiah Johnson).

Santiago-Hudson launched a national tour of Wilson’s “Jitney” — which he directs — in Washington on Sept. 13, and continues to perform a one-man show of “Lackawanna Blues,” his Obie Award-winning memoir (and 2005 HBO movie) that effectively launched this remarkable career back in 2001.

We spoke recently. An edited version of the interview:

Q: “David” is a coming of age story like “Lackawanna.” Is that what drew you to the role?

A: (Creator) Tarell Alvin McCraney and I have always expressed a desire to find a way to work together but our schedules never coincided. On this project, it finally worked out and came out wonderfully.

Q: Not be crass, but it seems like theater is what you care most about and TV is just a quick paycheck. True?

A: Not crass at all. It’s correct that theater is not only my first love but number one love as an artist. Theater is a place where I can realize my humanity in its fullest.

Q: I’m sure it would come as a surprise to fans of your many TV shows that you had such a long, close association with one of the great American playwrights, August Wilson. How did that come about?

A: It started with me witnessing "Ma Rainey’s Black Bottom" I was determined to find a way into one of his plays, even if it was me being the coffee boy … We immediately bonded. We also had similar upbringings, both biracial, and learned some of the lessons we had learned about life and liberty and the navigating of America from older black men who had faced arduous times … He’s largely responsible for (my career).

Q: It took you 11 years to get “Jitney” — which won a 2017 Tony for best revival — to Broadway, but diversity and inclusiveness now seem to be much better in theater, movies and TV. Is that true from your perspective?

A: You could ask the same question I asked everyone else when I walked in the room, after I put my heart and soul in this work. Wilson was arguably the greatest American playwright, without a doubt the greatest of the last two or three decades. What are we arguing about here! I wasn’t asking for money but for space I’m still trying to get another Wilson on Broadway and still facing ‘no no no.’ But I do think things have gotten better. We do now have showrunners of color, and producers. We don’t have studios that we run, and that’s where things have to change.

Q: I see you were in a 2008 TV movie called “Long Island Confidential.” What was that about?

A: It was actually a TV pilot, and a very good pilot that had a lot of problems. It was about a New York City police detective who worked on Long Island looking into various crimes. It was an interesting show.