CSI: Vegas executive producer Anthony Zuiker, the mastermind behind the blockbuster CSI franchise, is counting his lucky stars. For the super-producer, reuniting original stars William Petersen and Jorja Fox for a follow-up series has been surreal.

CBS’ latest CSI entry, which premiered 21 years to the day after the flagship series launched, follows Petersen’s Gil Grissom and Fox’s Sara Sidle as they use forensics to solve crimes and find out who framed their former Crime Lab boss, Jim Brass (Paul Guilfoyle), putting years of their work and the future of the Lab in jeopardy.

“So fun,” creator and executive producer Zuiker told ET when asked what it’s been like to revisit the world. “It was great to be back on set. It was great to see the new faces and the veteran faces. It was great to be back in Billy’s trailer arm-wrestling dialogue as usual, but it was cool. When they say ‘action,’ it’s happening. It brings you back to 2000 when it first started.”

Ahead of Wednesday’s new episode, Zuiker discussed restarting a sacred on-set ritual with Petersen and Fox on CSI: Vegas, going more personal with the storylines and why fans of the franchise should expect future cameos from the original CSI franchise if the show gets a season 2 pickup.

ET: What was the most intriguing part about revisiting Grissom and Sara in 2021 versus the early 2000s?

Anthony Zuiker: I think for me, I have a ritual with those two. I’m always the first face Billy sees when he comes to set. I will stand in front of his trailer, until he pulls up, with my script. I’ve been doing that for 16 seasons. And then once I get Billy’s dialogue, I’ll go knock on Jorja’s trailer and hear her feedback because sometimes his dialogue affects her dialogue. So that was a surreal ritual that I continued. And I think I’ve caught myself at times on set in the director’s chair with headsets on watching those two act and just marveling at the fact that it’s just so natural for them and how they could just snap back into the characters with such ease. It’s really a delight. They make it look so easy and it’s really watching the magic continue.

In the original CSI, it was never as big of a priority to see the characters’ home life. But on CSI: Vegas, there’s a much better sense of Grissom and Sara’s dynamic outside of work. Why did you want to plant the flag on the personal here and what that illuminates about these characters through their relationship?

Yeah, that’s a choice. That’s a Jason Tracey choice. (Tracey is the showrunner of CSI: Vegas.) We never brought characters home. We never really delved too deep into their personal lives. We never really had long runners like with the Lab being under scrutiny. That really wasn’t our show, but we decided to evolve the franchise into different areas that were new. So you will see a deeper dive into the puppy love relationship between Folsom and Allie. You’ll see some of the quibbles of Grissom and Sara with their long marriage. You’ll see those kinds of things. You’ll see the personal life of Paula Newsome’s character, Maxine, with her son. That’ll be opened up far earlier in the season than we’ve ever had before. It’s refreshing and it’s something new for us.

You have this long serialized mystery that the folks at the Crime Lab are trying to solve with Jim Brass being framed, yet also marrying that with the week-to-week procedural element with new cases. How has that been balancing both of those narratives in a way that fits together?

It was challenging. The purists, like myself, want the puzzle. We want the mystery that we want the solve. The longer arc is something new for us. We supported it because it’s new and because the behavior habits of our viewers, they like more serialized things in this generation. So it was definitely a balancing act. Will that happen next year, if we get picked up? I’m not sure. But the challenge is, the more you do longer storylines like that, the more forensics you take off the table. So we have to be careful not to take too much off the table with our A-side procedurals for the sake of B-runners. That was quite a tricky balancing act that we attempted to pull off all season.

What has surprised you the most?

I think what’s surprising is when I was in it in 2000 and started CSI, I didn’t really recognize how the cast gelled by episode 7 – that was a show called “Blood Drops” – because you’re in the thick of it and you don’t really pay attention to anything besides what’s in front of you. I want to say that episodes 4 and 5, meaning Wednesday and the Wednesday after, I think those were the two episodes where I called Jason and said, “I think this cast is really starting to gel as a family.” I think those were the two episodes where it hit me that they were starting to be funny and likable and jovial, and it felt like a family. The first three, they’re just trying to find their feet as actors. But I think [episodes] 4 and 5 were the cementing of the cast, in my opinion.

What can you preview in these next couple of episodes that you’re excited for viewers to see?

There’s two things. Episode 4 is called “Long Pig.” It really is a commitment to Allie’s character in her backstory. You’ll see her take an emotional dive in that episode, which is a new color for her. And then there’s a beat in episode 5 [titled “Let the Chips Fall”], where Folsom makes a forensic discovery. And it really is a tip of a hat to the original CSI. It’s just a physical gesture he does and has a light bulb go off that goes, “Ah, that’s what CSI is.” Those are two awesome moments coming up for [episodes] 4 and 5. If you print that and people read this, they’ll go, “Oh, that’s what Anthony’s talking about,” when they see it.

You’ve probably been asked many times over with the show returning and certain characters coming back about the possibility and potential for other familiar faces to swing by. Are there surprises like that in store?

There are no surprises in that category this season. But I will say that the CSI family, including Vegas, New York, Miami, Cyber, all of those conversations are wide open. I will be personally lobbying to bring somebody [specific] back from CSI, if we get a pickup. I think the fans would like to see some familiar faces. And if we do get a pickup, and we have a sit-down about what season 2 looks like, I’ll definitely be making a case for bringing familiar faces back, yeah.

Any hints you can share?

No, I definitely can’t mention names. But if I had to choose, it would be somebody from the original CSI cast to come back. That would be something I would definitely lobby for. And like I said, CSI’s family, so all four of those shows are wide open for possibilities. You’ve seen Chicago Fire, Chicago Med. You’ve seen all that work. They’ve done a great job at NBC packaging those shows and keeping those shows on the air. There’s no reason why we couldn’t do the same thing.

Is there anything else that you wanted to say about the season?

Look, there’s no guarantee we’ll get picked up. There’s no guarantee we’ll have Billy and Jorja back. What I will say is, every episode that they star in is special and to take full advantage of them on screen. It’s a luxury to have them back.

Does the finale feel like a bit of a wrap-up or is it also open-ended?

The finale keeps things open. It’s smart to do that. Things can change, people can change, cast members can change. It’s not the swan song that I wrote in the finale, where Grissom and Sara are on a boat in the sunset. That’s a finale. This keeps it a little bit open.