Cybill Shepherd is busy working back-to-back assignments these days – with her role as James Roday’s mother on “Psych” being unveiled in the show’s new season next month, another season of “The L Word” ahead, and two independent films.

With her three children off on their own and her home downsized, the 58-year-old star of film, TV and stage – who’s lived through her share of tempestuous times and diva accusations – sounds more mellow than in the past.  Is she?  “Oh, yes.  I think I was pretty mellow in the very beginning maybe, but success has a way of just hyping you up,” she candidly observes.  “It’s hard not to believe you’re going to stay at that level of everything – popularity, financial gain.  I’ve been around long enough I’ve seen it come and go, come and go.

“I think the thing that contributed to the wonderful activity in my career at this stage is ‘The L Word,’ which has been a really great opportunity for me in terms of publicity, fan response and work,” adds Cybill, whose daughter Clementine will also return on that Showtime series’ final season, which begins production next month.

Cybill recently completed the off-the-wall movie comedy “Barry Munday” with Patrick Wilson, Chloë Sevigny and Malcolm McDowell. Now she’s in Pennsylvania making “Another Harvest Moon.”

“It’s a multi-generational story with an amazing cast. Piper Laurie, Doris Roberts, Anne Meara, Richard Schiff, Ernest Borgnine… I can’t believe I’m getting a chance to work with Ernest Borgnine!  He’s 91, and he helped me with one of my lines yesterday,” she says of the beloved Oscar winner, who plays her father in the flick.

She’s been putting in 15-hour-plus days.  “It’s tough but I’m adapting.  It’s not about me, these hours.  It’s not someone trying to do something to me.  I’m not taking it personally,” she says.  “There’s a great camaraderie on this film.”

THE POT THICKENS: Elizabeth Perkins reports her character’s antagonistic relationship with Nancy Botwin, the pot selling mom played by Mary Louise Parker on “Weeds” “is going to change” as the just-launched new season of the Showtime series unfurls.

“I love it when we’re at odds because it’s so much fun to play,” says Perkins, who’s garnered two Golden Globe and Emmy nods for her portrayal of Celia Hodes on the show. “But we’re finally going to be in cahoots with each other.” She notes, “There were so many seasons of us being at odds, there was no place to go except for us to accept it’s fate we’re to be together. It’s kind of like having a sister you can’t stand and she’s not going to go away. From the moment last season when Nancy had to come to Celia and say ‘Look I need your house,’ Celia has had the upper hand. It’s sort of like Celia is family now whether you want her to be or not. She’s not going away and Nancy has to figure out a way to work with her.”

Perkins adds, “I love it because I think Celia is really madly in love with Nancy. I think that’s a facet of the relationship that will always be there. Celia’s just kind of like this puppy following Nancy around saying ‘Why won’t you love me?’ I don’t think that will ever change. I think it comes out of the general boredom with her own life. She gets really excited with this (marijuana) stuff.  I loved that moment last season when she’s with Conrad and he calls her ‘Gangster Barbie.’ I’m so excited to be part of the gang now.”

HOME AGAIN: “Reno: 911!” regular Wendi McLendon-Covey says she’s having a blast moonlighting at her old stomping grounds, The Groundlings comedy theater in Los Angeles. “I’m doing a really fun show at The Groundlings with Mindy Sterling, Michael McDonald from ‘MadTV,’ Kim Badgeley, Rachel Harris, Melissa McCarthy from ‘Samantha Who?’…a lot of the old Groundling alums that have gone on to be successful,” says the actress. “It’s called ‘Beverly Winwood Presents The Actors Showcase and it’s a send-up of all the bad actors’ showcases – and there are thousands — in Los Angeles. It’s a show that’s been going on and off for like seven years and its how the casting people found me for ‘Reno.’ It’s so much fun and it sells out within minutes. They keep adding more dates and now it sounds like it’s going to run Monday nights through July.

“It is a scream. We all play fictitious people who have taken acting classes from this Beverly Winwood person. Everybody gets up and does things that are inappropriate just like in a regular showcase. I’m playing a woman who danced in high school and 20 years later she’s feeling pretty confident she could be doing it again, so she chooses to play Cathy from ‘A Chorus Line.’ It is such a good time. I love looking out in the audience and seeing people gasping for air, or seeing that look of amused horror. It’s horrifying in the best way.”

AND THE CATCH IS…:  Interesting casting notice that went out the other day for a Travel Channel host for a show about cruising the world.  We hear that producers specifically have been seeking a female of multi-ethnic origin, along with travel experience, great energy, the ability to feel comfortable in different cultures, and a willingness to do her own hair and makeup.

And imagine the candidates who swarmed producers of a soon-to-shoot infomercial involving new cosmetic surgery techniques for face lifts, neck lifts and other goodies.  Per casting sources, they sought men and women, 39 to 65 years of age, to make 150 bucks a day plus $5,500-to-$9,500 in procedures.  No general anesthesia.