Meanwhile, CBS Entertainment president Kelly Kahl said the network would like to keep TV's No. 1 comedy for as long as possible.

The end of the road for CBS' The Big Bang Theory is coming into closer focus.

The nerdy series ranks as TV's most watched comedy among the advertiser-coveted adults 18-49 demographic and was renewed in March for its 11th and 12th seasons (48 episodes in total).

"We never really figured to be at year 11, let alone what's going to happen after 12. One could easily presume that would be the end of the series, but I'm just amazed we're here," co-creator Chuck Lorre told The Hollywood Reporter after presenting spinoff Young Sheldon to the press Tuesday at the Television Critics Association's summer press tour.

Big Bang Theory does not plot out storyline arcs in advance, a change from how most television shows are traditionally produced. Executive producer Steve Molaro — who recently stepped back as showrunner to focus on Young Sheldon — was more reluctant to address the show's future. "We look at one episode at a time, that's what we've been doing for the last 10 years and it's gotten us this far," he said.

Asked whether season 12 was the end game for the comedy, new CBS Entertainment president Kelly Kahl — making his debut on the TCA stage — offered a more open-ended approach to the future of the series.

"As long as we can go; 20 years. I hope to have it as long as we can," he told THR.

CBS and producers Warner Bros. Television have yet to announce any plans for the show's future.

The multicamera comedy comes with a hefty production cost of $10 million per episode. Sources note that CBS and WBTV are expected to jointly cover those costs. In its 10th season, Big Bang Theory remains a key property for CBS and WBTV, ranking as broadcast's No. 1 scripted series in total viewers (19 million) and the advertiser-coveted adults 18-49 demographic (5.1). The network also uses the comedy as a launchpad for new half-hours, with Young Sheldon scoring that honor this season.

In addition, syndicated repeats of the series on local cable stations and Turner-owned cable network TBS have helped bring in an estimated $1 billion in syndication revenue for the studio. Local TV deals have been extended beyond season eight, though TBS is unlikely to dole out the big bucks for seasons eight and beyond.

The original cast — Jim Parsons, Johnny Galecki, Kaley Cuoco, Kunal Nayyar and Simoon Helberg — took pay cuts to help co-stars Mayim Bialik and Melissa Rauch score salary parity for seasons 11 and 12. The five originals each signed rich new contracts that include 1.25 points off the backend, with Parsons and Galecki also extending their respective overall deals with producers Warner Bros. Television. Parsons is also executive producing and narrating CBS' straight-to-series prequel Young Sheldon, while Galecki's By the Book comedy was picked up to series and is slated for a midseason bow.

Meanwhile, with Molaro focusing on showrunning Young Sheldon, longtime exec producer Steve Holland has been tapped to take over as showrunner on the flagship series for season 11.