Mary Lynn Rajskub has gone from hilarious comedienne to a cult favorite actress. You may have spotted her making people laugh in series like The Larry Sanders Show and Mr. Show. Or you may have seen her helping save the day as computer expert Chloe O'Brian on 24. Now she has a regular role on CBS' new sitcom How To Be A Gentleman. Rajskub plays Janet, the "bossy sister" of struggling advice columnist Andrew (David Hornsby). She dropped by recently to chat about her return to comedy and her long history of making us laugh.

I'm sure everyone says "I loved you on 24," but I'm going to go back even further: I first remember you from a little half-hour called The Downer Channel.

You win the award. I've done a lot of jobs, a lot of people pull out Larry Sanders, no one pulls out The Downer Channel. That show had a lot of great material and a lot of great promise. I think it was one of those things where we didn't have time to figure it out. Shows need to find their way, and sketch shows like that even moreso, but they tend to get even less confidence in them. They almost never make it. We had Steve Martin executive producing and we had a good team, but I think there was way too much pressure.

(*Author's note: you can download the hilarious theme song to The Downer Channel from Wavethemes. You'll thank me later.)

After 24, do you still see yourself as primarily a comedic actress?

I do. 24 really did so much for me in a lot of different ways. Professionally, in terms of character, but it also boosted my confidence as an actor. Even when I do stand-up, it's all a form of acting to me. I'm not a traditional stand-up where I sit around and tell jokes all day. I recently did a guest spot on Modern Family, and Steve Levitan, the creator of that, comes and sits right next to me and has a grin on his face and goes, "Can you believe you were on a drama for six years?"

Do you find comedy more or less difficult than drama? Drama tackles tougher stuff, but it seems a lot more universal than comedy.

I was really scared to start doing 24, and now coming out of it, I'm a little scared to get back into comedy. It's already happened a few times on the How To Be A Gentleman set where [I] want to like find the word, or find how I'm going to say this. You're not going to take that huge pause. I really learned how to do that on 24, especially with the dramatic looks at the end, because I knew they were going into a [graphic] box or something. We don't have any of that. It's much more ensemble, much more rhythmic. Everything is just a step lighter.

What attracted you to How To Be A Gentleman?

I knew I wanted to do comedy, but I wasn't exactly sure what or how, and I was developing stuff on my own. It just came up, and it's great. David Hornsby is hilarious. The script was really kind of cool, and it was just a bonus when I found out who the rest of the cast is going to be.

Tell us about your character, Janet. Who is she?

I work at the Science and Technology Museum in Chicago. I am the sister of the main character, David Hornsby's character. He's too much of a gentleman and too mannered, and I think he's kind of a loser. I really care about him and I want him to not be such a loser, get a girlfriend and have a life. I kind of tell the people in my life what to do. My husband is [played by] Rhys Darby. Rhys, just playing scenes with him, he's so damn funny.

Do you have a favorite moment from your time on the show so far?

There was an incident where I fell off a rock climbing wall because my husband was looking at a girl. I like it. It was very light and humorous.  I kind of make fun of him, but we also love each other. He's from New Zealand and there's one scene where he thinks he's going to be deported. I start freaking out because I think it's going to be a test and I can't take tests. It's very different.

Do you have a dream role or project that you'd love to do someday?

It could be the 24 movie, it could be Chloe, or it could be some other movie, [but] I'd like to be an action star in a movie, who's just like a badass.

What TV shows would you recommend to our readers?

I really love Breaking Bad and True Blood. Those are probably my two favorite shows. We watch a little Boardwalk Empire, and we're waiting for Mad Men to get back. You know, my husband got me watching Big Brother of all things. Sooner or later, everyone's going to cave to reality.

My thanks to Mary Lynn Rajskub for this interview! Follow her on Twitter (@rajskub). How To Be A Gentleman arrives on CBS in late September.