Diane Haithman is a Deadline contributor.

This morning members of the press got a first look at the first episode of CBSUnder The Dome at CBS Studios in Studio City. The heavily promoted 13-episode summer series from Steven Spielberg and Stephen King premieres June 24 at 10 PM. But there also is an interesting story beneath Under: The series, from Lost veteran Brian K. Vaughan (who developed Under The Dome with co-creator Stephen King, whose dystopian novel inspired the show) and executive producer Neal Baer, took a long journey from concept-in-development at Showtime to CBS.

A little history: A few years ago, Vaughan had a meeting at DreamWorks, which had the rights to King’s novel. “They said they were thinking about taking it to Showtime to do an ongoing series,” Vaughan says. “It was in development for a really long time at Showtime and they were terrific. But I think when it came time to pull the trigger, they thought it was not a perfect fit for the direction that Showtime is headed. But [Showtime president] David Nevins thought: ‘This is a terrific script. I’m going to call [CBS entertainment president] Nina Tassler and see if it’s a better fit for CBS.’ ”

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Baer, who has deal with CBS, was brought in by Tassler. “I had worked with Spielberg on ER, so that was a great reunion,” he says.

Vaughan and Baer object to calling the resulting Under The Dome a miniseries or even a limited series. Baer says the idea is to bring it back “for many summers” for 13 serialized episodes each time. Says Vaughan: “At the very beginning, CBS said: ‘We don’t want to cede the summer to cable. We want to compete with them. We want to do something that’s dark and edgy and a little bit more complicated.’ ”

Vaughan and Baer noted that in the cable world, 13 episodes or less is considered a season, not a limited run. Said Baer, “Cable doesn’t talk about itself in terms of limited series. The format is changing so rapidly.” He said the networks are following suit. Baer cited as an example Fox’s recently announced event series for fall 2014, M. Night Shyamalan’s Wayward Pines starring Matt Dillon and Melissa Leo. Adds Baer: “Maybe that’s pinned to [ABC’s] Scandal, which started as sort of limited run, but as it grew it grew in number. It looks like the broadcast networks are taking more chances, trying different formats and approaches.” As previously announced, Under The Dome episodes will stream four days after airing on CBS on Amazon Prime’s VOD service.

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Baer, a veteran whose credits include the long-running ER and Law & Order: SVU, says TV shows must adapt to a viewership that is no longer ruled by time slots. “When Brian did Lost and I did ER, for instance, those were water-cooler shows and people talked the next day — 40 million viewers, that just can’t happen anymore. We just hope with this show people will talk all the time.”

There was a story “spoiler” of sorts at the Under The Dome offices in Sherman Oaks: On a coffee table is a scale model of the dome that in the sci-fi series falls over Chester’s Mill and cuts the small town off from the rest of the world. Baer said the whimsical mini Chester’s Mill (complete with plastic farm animals and picket fences built by production assistants) offers gruesome story clues. “If you look right here, this is half a person,” Baer said, pointing out a bloody streak by an edge of the “dome,” which here looks like a glass mixing bowl. “And we will give something away: In Episode 2, that person was picnicking. And you can see the blood track here. We think his girlfriend dragged his torso away. She was on the outside.”

On the inside of the dome is the other half of the unfortunate picnicker. And “we get the dog,” Baer said of the picnickers’ canine companion. “And the dog becomes Truman on our show.”