Waltz and Tarantino reunited for 2012’s Django Unchained, which added more hardware to Waltz’s trophy case as he took home his second best supporting actor Oscar for the role of Dr. King Schultz. To this day, Waltz is the only actor to achieve Oscar glory for Tarantino.

Waltz is now making his return to the big screen as Dr. Dyson Ido in Alita: Battle Angel, a cyberpunk action film helmed by fellow Tarantino ally and collaborator Robert Rodriguez. Alita: Battle Angel combines the ambitious world building of producer and co-screenwriter James Cameron with the independent sensibilities of Rodriguez to tell a story about a revived female cyborg who battles amnesia during a journey of self-discovery. Despite the grand scale of the film, Alita relied on virtually no green screen.

“Everything else was built; everything else was there. It is probably the best set that I’ve ever seen,” Waltz told The Hollywood Reporter.

When asked if he develops backstories for his characters, including Alita’s Dr. Ido, Waltz said, “I’m a little hesitant to discuss these things, because I don’t think it should be interesting from the audience’s perspective. To disclose intimate details –– and backstories are the most personal and the most intimate details –– is something I feel is counterproductive for both sides, the actor and the audience.”

In a recent conversation with THR, Waltz elaborated on why he’s immensely private regarding his characters, including his process of getting into character. He also reflected on his first Oscar win in 2010, and the memory that has stuck with him to this day.

When you read a script and ultimately commit to a project such as Alita: Battle Angel, is the decision based mostly on instinct, or do you weigh the various pros and cons?

What if my instincts are wrong? Then what? Instinct plays a part in this, of course, and it should. But it shouldn’t be the only thing. I am a very skeptical person, and I am not 100 percent convinced that first impressions are always entirely reliable. One should never ignore them, but to further scrutinize them is very often a rewarding thing to do. To apply analysis, meaning a rational approach, is not wrong, and that doesn’t mean you have to override your instincts. Sometimes you discover stuff that you haven’t seen by looking at it from an entirely instinctual perspective, and that is what makes it really interesting.

Of the scripts you receive, what approximate percentage of them actually capture you enough to keep reading until the end?

I don’t like to quantify, so I don’t know. I like to really concentrate on the story. It all depends on your momentary state of existence, what you’re interested in, and that interest changes. To say “Well, probably of the stuff that I get… 20 percent,” I’m just not sure. It kind of falls under the same category as first impression and instinct, so it wouldn’t be a reliable figure. If you put the bar really high, you may end up with nothing in the end. If you kind of accept indiscriminately, you may end up doing anything or everything. So it really all depends on the moment, I’m afraid to say.

Alita: Battle Angel is one of only a few blockbuster films where the hero is essentially a teenage girl. You’re a father to a young daughter. Did that factor in your decision to be a part of Alita?

No, that’s a great element in the story, especially the dynamic between the characters [Rosa Salazar’s Alita and Waltz’s Dr. Ido], but that it relates to my life is not necessarily one of the pivotal decision-making points for me. In a way, my imagination is being asked for and called upon, not so much my what we would all call reality.

Your character, Dr. Ido, along with Jennifer Connelly’s Chiren, are examples of how grief affects everyone differently. In terms of process and developing the character, did you channel grief from your own life into the character, or did you let your performance of the text elicit such feelings?

All of that happens –– or not. If it happens, it’s good, because you don’t really have to think too much about it. If it doesn’t, that’s where it becomes interesting. Whether or not you’re successful in your channeling, we’re all the product of our experiences; we’re all the outcome of our past. We have no choice about that. When someone says, “They’re always playing themselves,” well, yeah…what other choice do they have? We rely on and we communicate not only with the thing itself but with what brought us to that point in time. What do we do as actors if we get stuck? It sounds like it’s a thing you can easily produce, but if we can’t channel, as you put it, that’s where technique and imagination are required. And then maybe you discover by getting things in motion and into a new flow that, yes, it was as Laurence Olivier called it [to Dustin Hoffman], “My dear boy, why don’t you just try acting?”

Are you still discovering new aspects of your acting ability that surprise you, or do you know what tools you have at your disposal by now?

Both. Of course, the tools I should know by now. If I didn’t, I’d have to go to school very quickly. That doesn’t mean that the application of those tools cannot be surprising. Yet we really have to differentiate very clearly and very precisely between the process and the result. I’m not involved in the result. That’s why I like that you called them tools; I am involved in the application of tools, whatever they may be. You practice handling those tools, and after a while, you don’t need to concentrate on the handling of the tools that much. The outcome, whether that’s surprising or not, is more for you as an audience to decide than for me as the craftsperson who’s wielding the tools.

In general, do you still create backstories for all of your characters, including Dr. Ido?

I’m a little hesitant to discuss these things, because I don’t think it should be interesting from the audience’s perspective. It may be interesting from the actor’s perspective, but it’s very personal and, in a way, intimate. It’s an individual decision as far as what you do, or maybe you don’t do, by coming to a decision. To bring us back to instinct, maybe you do it by instinct, which is fine if the instinct takes you there. Yet I shy away from the discussion of it in public. To disclose intimate details –– and backstories are the most personal and the most intimate details –– is something I feel is counterproductive for both sides: the actor and the audience. The audience should really be involved in experiencing the story from their perspective and not so much trying to evaluate something that they cannot possibly fathom, nor should they.

Do you ever think or dream about your past characters? Do they ever creep back into your psyche when you least expect it?

No, I don’t even talk about them. Never, really.

Because Alita: Battle Angel required an extensive visual effects process, mainly for the performance capture characters, was acting on this particular set more challenging, since your imagination was likely working in overdrive?

On Alita, there was no green screen. Maybe three details were added later with green screen. Everything else was built; everything else was there. It is probably the best set that I’ve ever seen. In our specific case, we really didn’t have to deal with green screens, yet it should not really make a difference, because you need to employ your imagination either which way, whether it’s green screen or detailed reality. It’s not a sudden reality shift like a hallucination. The myth about the actor becoming the character is more than dubious, I find, because the actor still needs to do what is being asked of them in a situation that will hardly ever be congruous with their life. So imagination is always employed.

It’s Oscar season, and your first Oscar win for Inglourious Basterds was almost nine years ago. Filmmaker Richard Linklater often talks about memory and how we’re more likely to remember the small moments that surround the big moments, such as the car ride home from graduation, than the big moments themselves. On that note, is there a small moment or memory that has stuck with you from the 2010 Oscars besides the big moments of hearing your name called and giving a speech?

Those are the memories that vanish, as Richard Linklater refers to them. I have one little memory where a very sweet, angelic person appeared in front of me. She said to me, “You will not remember any of this, but trust me, I’ll take you by your hand and I’ll lead you out of here.” (Laughs) And that I remember vividly.