"Whose Line is it Anway?" returns to the CW on March 21, having scored successfully enough in last summer's run to be granted a 24-episode season. Improv lovers will also be glad to know that "Whose Line" stars Colin Mochrie and Brad Sherwood, who've been taking their "Colin Mochrie & Brad Sherwood: Two Man Group" improv show all around North America, have an hour-long special derived from those live shows landing on the CW March 14.

Mochrie spent seven years as a regular on the British version of "Whose Line" and seven seasons on the first American version with Drew Carey. He's been seen on subsequent improv shows like "Drew Carey's Green Screen" and "Trust Us With Your Life." Sherwood recurred for three seasons of the Brit show and was on throughout the U.S. run. That's a lot of improvising — but both tell us they love the improv life as much, or more, than ever. They're rarin' to keep working with fellow "Whose Line" stalwarts Ryan Stiles and Wayne Brady, and host Aisha Tyler.

We collected some improv insights from the top team on a recent afternoon.

Q: How do you compare the hosts you've worked with?

Colin: Clive (Anderson) was the quintessential Brit. Very witty, very dry, sort of liked to keep things going and stay in charge. Drew was sort of your typical American, your sort of every guy. What was great about him was, we gave him as much [grief] as he gave us. And with Aisha, she's sassy, and I think we're trying to figure out how to joke about her. It's hard when you're up against a beautiful woman who is also a nerd, trying to find out just exactly how to attack her.

Brad: I've known Aisha forever. I used to work with an improv group in L.A. who performed every Sunday at the Laugh Factory and for awhile she was the host of the Sunday night show. That was back in the '90s so we go waaaay back. She's great.

Q: Do you find that men and women approach improv differently, or the same?

Colin: Oh, this will get me into trouble. I'd say, the women who do the best in improv don't improvise as women. They improvise as people. They don't use their sex, like they don't do bimbo characters. They play things off of their intelligence. They don't think about, well, I'm a woman, I have to bring a woman's point of view. They're just funny. That's when women tend to do the best at improv. They tend to do more characters than guys, I would say. Guys tend to get a little more shticky and go for the joke. I think women are better at doing great characters and keeping the narrative going.

Q: When you started on "Whose Line," could you have imagined it going this long in so many different homes — in addition to your stage shows?

Brad: It's kind of fun. We're the old vagabonds that move from channel to channel. We're like Frankenstein. We can't be killed. Someone will say, 'Oh, that was a great show. Let's put it on again.' And then they do, and they get great ratings and people fall in love with us all over again. It's like seeing a comedy show and a magic show at the same time, because we are literally creating the content out of thin air when we get up on stage. It's completely fresh because the show is different each night. We get like first night jitters because we never know what is going to happen.

Colin: You know, the greatest thing about 'Whose Line's' success is that it brought improv into the forefront of the arts. It was sort of still an unknown thing when 'Whose Line' started, and now high schools, elementary schools, colleges — they all have some sort of improv program going, and God bless 'em.

Brad: Kids now have grown up watching improv because they saw it on 'Whose Line.' When I was a kid, the occasional improv group might have existed in a comedy club. But now everybody knows what improv is, which is kind of cool.

Q: It must be rewarding to be a trailblazer.

Brad: We're like the Mount Rushmore of improv comedy.

Q: Do you ever visit those classes and get treated like rock stars?

Brad: We've been asked, when we've come into towns where there's a university with improv as part of its theater program, to come in and teach a master class. So Colin and I have done that, and it's so much fun.

Q: Would you ever rotate college students into the show?

Brad: Let's not get carried away. Were not going to have a college week like 'Jeopardy!'

Q: Do you find that audiences are more savvy about how to play with you, providing scenarios for the games?

Colin: No. I wish they were. How many times can you get 'Proctologist' as a suggestion? On our live tour, Brad and I spend most of our time trying to get our audiences to sort of up their game a bit, try to figures out ways to ask for suggestions.

Q: Do we get to see evidence of that in your special?

Colin: Yeah. It's pretty much exactly what our show is.

Q: Was it a hard special to put together? It's not like you could pick the best set — since each appearance is different.

Colin: It was really up to our editor to put that together, with our input. Whatever games worked best were the ones that we put in. You know, an improv show at its best can be terrifying, because it depends on the audience; it depends on that particular night. I think it was great that we did this in Milwaukee. For some reason, Milwaukee just loves us. It's our 10th year in a row there. I think it went better than we expected because we're both kind of pessimists.

Q: Why does Milwaukee love you, do you think? The Midwesternness? The beer?

Colin: I think it's just that they're a highly intelligent group of people.

Q: What about other places, other countries?

Colin: In Canada, we've been pretty lucky — every province we've hit has been fine. Australia was wonderful a few months ago. India — we were a little nervous about it because of course it's an entirely different culture there. There's that fear, 'Will they get our stuff?' — even though our show is very popular there. Then came that first suggestion when we asked the audience for something, and we got 'Fart.' So we felt pretty confident.

Really, we just do what we do. We can't worry about trying to please an audience. I think the fans of the show are pretty boisterous people.

Q: Bob Newhart said sometimes he watches an old episode of one of his series and can't remember doing it. Does that kind of thing happen to you?

Brad: I would say that phenomenon is even more true of doing an improv show, because you didn't have lines to memorize. You were literally flying by the seat of your pants, so you have a short-term memory of what was going on that night, as you're doing it, because you had nothing planned. When I see old 'Whose Line' segments on TV, it's like a whole new experience. I have no idea what I'm going to say, it's just as much of a surprise to me as anybody else.