The dome may be coming down, but that doesn't mean it's the end of CBS' Under the Dome.

CBS Entertainment Chairman Nina Tassler told reporters at the Television Critics Association fall previews on Monday that while no decision has been made about Season 4, they weren't ruling it out. "The dome is coming down at the end of this season, but that opens up a host of other storytelling opportunities," Tassler said.

The question came as Tassler was being asked about the overall performance of CBS' summer programming. While Tassler acknowledged it's been a tougher summer, she said she is happy with the network's summer strategy. "We went into summer to have more original programming on air," she said. "Zoo is the No. 1 scripted show, Dome is the No. 2 scripted show, and Extant is No. 4. ... The shows are still performing. ... [and] these stream well on Amazon."

Fall Preview: Get scoop on your favorite returning showsTassler also acknowledged that CBS remains committed to summer programming. The network recently ordered the comic thriller series BrainDead from The Good Wife executive producers Robert and Michelle King, which will air next summer.

As for the network's other summer programming, long-running reality hit Big Brother, Tassler answered criticism that the show has failed to cast anyone over the age of 40 the past several seasons by highlighting the type of cast that made the cut this season. (This year featured the first-ever transgender houseguest.) "We will absolutely have characters over 40 [in the future]" Tassler said. "We didn't this year, but having the type of cast we did this year was unique and made a statement about the quality of people we put in the house."

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