It’s been 28 years since David Koepp wrote a screenplay about dinosaurs. As you probably know, Koepp was the screenwriter (along with author Michael Crichton) for Steven Spielberg’s original hit “Jurassic Park.” He then wrote the script for Spielberg’s 1997 sequel, “The Lost World: Jurassic Park.”

And then, well, he was out of ideas when it came to dinosaurs. When Joe Johnston’s “Jurassic Park III” came around, it was time to let someone else take a shot at it. Koepp has stayed peripherally involved in the “Jurassic World” movies since, offering some notes here and there when asked, but as Koepp told IndieWire, there was nothing of real consequence.

This all changes with “Jurassic World: Rebirth.” It was Spielberg himself who called Koepp and urged him to return to the cinematic world he helped create over 30 years ago. And what Koepp found appealing was that it seemed like a perfect time in the series to reset with new characters and a new story. (Koepp makes it clear this is not at all a reboot. The events of the previous three films still took place. He’s pretty adamant he hates it when franchises decide to excise previous films.)

In “Jurassic World: Rebirth,” dinosaurs are still free in the world and are thriving around the equator. A pharmaceutical executive of questionable ethics, Martin Krebs (Rupert Friend), has determined that certain dinosaurs hold the key to ending heart disease in humans, which would mean trillions of dollars to his company. He puts together a team (which includes Scarlett Johansson, Mahershala Ali, and Jonathan Bailey) to travel to an area with a high density of these particular dinosaurs in an attempt to acquire the samples he needs. (As you might expect, this all winds up being pretty dangerous and more than one human gets eaten by dinosaurs.)

Ahead, Koepp explains why he was hesitant to return to the “Jurassic” movies and was worried about being “a sad sack.” But he also explains why he now feels rejuvenated, where the franchise could go from here, and if he’d want to write more “Jurassic” movies in the future. (The answer is “yes, he does.”) 

The following interview has been edited and condensed for clarity and length.

Hmmm, well… no. Because they are not trying to kill me. So, I feel better about it. After the first two, they were making a third one and there was some talk about coming in and I said, “I don’t have any other ideas.”

I just didn’t have any ideas. I just did two of them and I feel like I said everything I had to say about dinosaurs.

Yeah, yeah, try him, he’ll be good. And then 27 years go by and Steven Spielberg calls and asks if I’d ever want to do another one. I watched them all, of course. And I read the scripts and he’d ask for an opinion from time to time and I’d tell him what I thought. It felt to me like every three movies, so far, there’s been three movies, new characters, new ideas. So here we are, so I go, “Can we do new characters and new ideas?” Because “Dominion” brought things to such a rousing conclusion.

So, can we now — not deny the events of the previous films, because I hate that — but now say, here are the consequences. The world has changed and here’s how. And Steven said, yeah, let’s just let our imaginations run wild. And the ideas started to flow and I was like, this is great. I was worried about trying to pick up a tone I had last done 30 years ago. But it came back pretty quickly! I had a ball writing it.

I wanted to pick up the tone of the first movie.

“The Lost World” is a sequel, so it got darker.

It does get darker. There’s nothing you can do. I don’t know why, but they do. I wanted to pick up the tone of the original because I wanted to have fun. I wanted to recapture that, but was that something I could do when I as 30, but not necessarily now.

I reread both of the Crichton novels. Which was great.

Since I was working on them.

It felt surprisingly familiar. But the tone the Steven’s first movie hit was a combination of Crichton and Spielberg’s. Those two worldviews are different. One is darker, one is lighter, that’s just the way it is. And mine, particularly some of the humor. The way to recapture that tone was to get the band back together: Crichton, Spielberg, and me working on the thing. One of us, obviously, posthumously. I was worried about it, but I felt like I was able to recapture it right away. And I didn’t feel that much different than when I was doing the first one.

Yes. And it’s in the new movie. The raft scene. I wanted to use it before, but it didn’t fit the structure or the budget. And CG was so new, a T-Rex swimming? In 1992 water was still really difficult to do with CG. Not anymore. So that was going in. I’ll structure the whole movie around it if I have to.

Well, it wasn’t the start. But it was close. But, also, there was so much good science. There’s 800 pages of well-researched material in the two novels. And there’s a bunch of science I wanted to use. There are some lines in the movie that are straight out of the books and that was really helpful. I can do research myself, but it will never be as good and inventive as Crichton.

It’s something I considered. You know, it’s bad luck to talk about a sequel before you see how the world feels about my first try. But, yes, you could use these characters or it could be… did you read the novel “World War Z”? I recommend it highly. I see why they couldn’t do a movie that way, but every chapter goes to a different place around the world. You don’t follow a character throughout. And I always thought that would be interesting for a movie series. Every movie is different and a different place around the world. And one could do that with this. You could have all new characters and set it someplace else.

I would.

I was afraid of going in and feeling like a sad sack trying to recapture a feeling I had 30 years ago — that was appropriate to who I was then but not appropriate to who I am now And I was very happy to see, that within a few days of starting writing, it was totally appropriate. I really like that feeling.

It’s lovely!

It was tricky to write because, you know, how much of a mating scene are we talking about? How “Jurassic Pork” are we going to go with this?

There certainly is. In one draft of the script I wrote, “They approach the dinosaurs in the field. Let’s just put it this way, they have eight legs between them but only six are on the ground.”

I did.

Yeah, I turned it in. I thought it was funny!

But, it’s not appropriate.

How much do you love writing a character you know is going to be eaten by a dinosaur?

Well, sometimes you don’t know who is going to get eaten. Some of the you know, clearly. It’s fun knowing their fate. You try to hide it. But when there are only nine characters in your movie, you are pretty sure who might make it and who might not. When and how that occurs is another surprise. Sometimes it’s surprising to me, too.

How so?

I had planned on the Atwater character [Ed Skrein] to be around a lot longer. He had a whole other thing where he fell in league with Krebs, betraying people. And I was just typing one day and the thing leaped out of the water and ate him and I’m like, well, he’s gone.

I’m curious what you think you bring back to this franchise that may have been missing or different in the last three?

Well, in some ways I think my job was easier by virtue of our premise of “they can’t survive.” You’ve done something that’s not going to work. What that premise does is it makes them special again. I think they told a very large and very ambitious story over three movies where dinosaurs spread throughout the world. Once that happened, you can go anywhere in the world and you can have as many crazy dinosaur situations as you want. I was more limited. I find limitations freeing. I always like a story that takes place in 48 hours or they never leave the house. I like those limitations because, within them, what ideas can you come up with? So I think we actually had an easier time than the three “Jurassic World” movies because they got so big and that becomes hard to work with.

You do have a plot about splicing genetic codes to make new dinosaurs because, “audiences get bored seeing the same thing and want something new.” Yeah, I feel you’re trying to say something there.

Yeah, a little self-reference going on there, as a pan over to the “Jurassic Park” lunchbox and pajamas. Yeah, that is valid. You know, in the first movie I was struck by the irony that I’m writing a movie about greedy theme park people for … Universal, a profitable theme park company. Crichton’s idea was kind of meta. So, things get like that.

Universal Pictures will release “Jurassic World: Rebirth” in theaters on Wednesday, July 2.