"Under the Dome" season 2 air date is almost two months away, and new spoilers reveal that a "transformation" is coming to our favorite characters, including Big Jim, Barbie, Joe, and Norrie! Also, Stephen King will make a cameo in the premiere!

"This is a season of transformation," executive producer Neal Baer told USA Today. "Last year was a season of secrets being revealed about our characters. Now, they really have to cope with the ramifications of what this all means, since it doesn't look like they're getting out any time soon."

According to USA Today, "Under the Dome," based on Stephen King's novel of the same name, was the most-watched scripted summer series in 21 years, averaging 15.1 million viewers.

After the air date of "Under the Dome" season 2, you'll catch a glimpse of King himself: the author wrote the second season's first episode, "Heads Will Roll," and will be seen in a cameo appearance in the town's diner.

"It was fantastic to work directly with Stephen. He's been a real hero of mine and now I get to work with him," Baer said.

In the cameo, Stephen King, who has made brief appearances in other adapted works, "is just a citizen of Chester's Mill for at least the moment."

In the promo trailer video for "Under the Dome" season 2, which was released Friday (March 14) by CBS, executive producers Baer and Brian K. Vaughan gave a spoiler chat.

"The second season is going to take us to places where the book never got to go ... Stephen King gave us some ideas we never imagined," Vaughn said.

"We're really excited because [King] is bringing his usual twists and turns and shocking events," says Baer, of the book's author. "At the end of last season, our characters found out the dome came from another world. The dome is actually here to protect them," Vaughn added.

The promo trailer also teases the two deaths in the season premiere and new characters including Junior's uncle and a young school teacher, Zap2it.com reports.

As we previously reported, "Under the Dome" season 2's cast introduced newcomer Grace Victoria Cox, who will play Melanie, Joe's new love interest. The CBS series also recently added "CSI: NY" star Eddie Cahill and "Misfits" alum Karla Crome as new series regulars, most likely in preparation for the two "favorites" that are soon to be killed off in season 2.

"Under the Dome" returns Monday, June 30 at 10 p.m. ET/PT on CBS.