Jenna Elfman stars in "Imaginary Mary"

A pair of well-known comedians teams up for ABC's latest addition to its family-friendly prime-time lineup. Jenna Elfman, best known for playing the titular Dharma in "Dharma & Greg," and Rachel Dratch, famous for her years-long turn on "Saturday Night Live," star in the alphabet network's "Imaginary Mary," a new comedy that premieres Wednesday, March 29.

Elfman is easily recognizable as she steps into the role of Alice, a career-driven, fiercely independent woman whose priorities suddenly change when she falls head over heels in love with Ben (Stephen Schneider, "Broad City"), a divorcé with three kids: Andy (Nicholas Coombe, "Pants on Fire," 2014), Dora (Matreya Scarrwener, "Strange Empire") and Bunny (Erica Tremblay, "Before I Fall," 2017). Dratch, on the other hand, is only distinguishable by her voice, which she lends to the titular Mary, a fuzzy little creature who is white with blue spots and pink eyebrows.

Mary is a figment of Alice's imagination, concocted when the latter was a child to help deal with tough situations. Now, Alice stares down another tough challenge -- sudden motherhood -- and her little friend is back to try to help make things better. The problem is, though, Mary seems to have a penchant for stirring up trouble.

The 45-year-old Elfman, who has two kids herself, owns her role in "Imaginary Mary," even though the gig came with its own set of challenges. Not only is Mary imaginary in the show, but she's also CGI, which means Elfman is acting with literally nothing every time the two characters interact. It's not something she's unfamiliar with -- she starred opposite Brendan Fraser ("The Mummy," 1999) in the live-action/CGI blended film "Looney Tunes: Back in Action" in 2003 -- but "Imaginary Mary" takes a completely different approach to filming these important scenes.

"When we were filming 'Looney Tunes,' we had men in green suits, greenscreens, green little balls on sticks. There was a lot of, in the real world, greenscreen elements when we were filming," she told reporters at the Television Critics Association winter press tour. "This, because it's CGI, is a whole different sort of approach to animation. We had rehearsal with a stuffed, life-size puppet, and we had an amazing puppeteer, so we would rehearse with her."

Things get fun and interesting when it comes to actually shooting the scenes. "We would film one take with the puppet so that the animators had a reference for her in that live space. Then, they would take her away, and there would be nothing. So I didn't even have a green ball. I had nothing. It was like nothing, an independent chair. And then she'd be walking across the room, and she'd hop up on furniture, and then she'd come near me. ... It was actually a really great challenge comedically to maintain the scene with [Mary], but that's how it was different: I literally had no reference except during rehearsal."

Matreya Scarrwener as seen in "Imaginary Mary"

Dratch is on the other end of things. She does her work in New York, after everything is filmed, and is able to go with the flow of the scene as she sees them. She told the TCA press tour: "I have the freedom to go crazy."

And while it may seem crazy (and perhaps expensive) to do a live-action/CGI TV show, it isn't the first time recently that the main networks have blended animation with real people. Fox debuted a sitcom in September called "Son of Zorn," which saw Jason Sudeikis (another "Saturday Night Live" alum) voice a barbarian warrior from a fictional island opposite Johnny Pemberton ("21 Jump Street," 2012), Cheryl Hines ("Curb Your Enthusiasm") and Tim Meadows ("Mean Girls," 2004).

Still, it remains to be seen if "Imaginary Mary" will fit seamlessly into ABC's packed family-friendly lineup. Its episode order was slashed from 13 to nine in September of last year, but it's sliding into a slot on a strong day -- Wednesdays on ABC feature the likes of "The Goldbergs," "Modern Family" and "Black-ish," all acclaimed shows, with the latter two taking home a Golden Globe apiece ("Modern Family" also has 22 Emmys to its name).

Every so often, we all have a little voice in our heads pushing us to make decisions one way or another. For Alice, that little voice comes to life in the form of her childhood imaginary friend, Mary, who helps her when she jumps into instant motherhood. Elfman is back in prime time after a three-year hiatus as Alice, and Dratch lends her comedic timing and infectious personality to the little white-and-blue made-up creature Mary. Catch the series premiere of "Imaginary Mary" when it airs Wednesday, March 29, on ABC.