Nina Tassler, the chairperson of CBS Entertainment, had a lot of good news to share on Monday during the Television Critics Association press tour held in Pasadena, such as updates on the upcoming 'Supergirl' series, the renewal of three of CBS' top shows, and Stephen Colbert's debut.

During her exec session, Tassler immediately shared that CBS TV Studios will be renewing three of its top-ranked shows, 'NCIS: New Orleans', 'Scorpion' and 'Madam Secretary', with some others still under consideration, such as 'The McCarthys' and 'Stalker'.

She also shared that development on 'Supergirl' alongside writer Greg Berlanti and Warner Bros. TV is steadily progressing, and expressed high hopes after she and the team fell in love with the pitch.

"She embodied so many of the characteristics of classic female heroines on the network," Tassler stated.

She added that the costume is already completed, thanks to designer Colleen Atwood, but casting for the heroine was still underway. "We're looking for quality, charisma. She's got to be the everywoman," she said.

Tassler also talked about their plans for Colbert and 'The Late Show', saying they have already set a debut date for Sept. 8.

She shared they were still building a new set and planning a celebratory farewell for David Letterman, who will be parting with the show in May. She said, "For everyone at CBS, it will be very hard to say goodbye."

She didn't share much about what Colbert is planning for the show though, saying that it all depends on Colbert. "We're waiting for him to come to us and say what he has in mind. It's really a discovery process for him," she said.

Tassler remained vague on news of a possible 'Two and a Half Men' return for Charlie Sheen though.

The actor has been vocal about his desire to return to the show and when asked about it, Tassler diverted to talk of showrunner Chuck Lorre.

"Chuck is an extraordinary showrunner. I can promise you that there will be a lot of surprises and out of respect for Chuck, and this is a direct quote, he has promised to deliver what he's calling 'a mystery sandwich'," she said.