AJ Cook AJ Cook

Check one off the wish list for A.J. Cook. After seven seasons, the Criminal Minds star's dream has come true: She's getting beat up.

"My wish was granted! I was so excited when I got the script," she tells TVGuide.com. "It was like a kid in a candy store moment. I was just super giddy about it."

Check out photos from Criminal Minds

Cook will show off her combat chops on Wednesday's episode (9/8c, CBS) when JJ faces off with an unsub who's been leaving dead bodies in lifeguard towers. And frankly, if you ask Cook, it's been a long time coming. After all, half the cast has been tortured and battered by the likes of C. Thomas Howell

, James Van Der Beek and Luke Perry already."It started out as a joke. I guess there was a fan video put together with all the action and everyone getting beat up and shot, and we're like, 'JJ's done nothing but shoot a dog [in Season 2's "The Big Game"]. That was the most danger she's faced! It's her turn!'" Cook says. "It was that realization it's my time to get beat up — it's kind of like a rite of passage on the show — and then I really started pushing it."Not that she had to do too much begging. The producers and writers, who sit down with the actors before every season to chat and brainstorm ideas, were happy to fulfill her request, especially since JJ is now a full-fledged profiler. "It makes sense now that she's in the field more. I think we didn't do it earlier this season because she had to get used to being back and having [her son] Henry at home," Cook says, referring to the cast upheaval last season when CBS dropped her and Paget Brewster before rehiring them this year. "But you'll see, there's no hesitation or anything with her when she confronts [the unsub]. I don't know what people think [JJ's fighting skills] might be, but she's pretty badass — I'm just saying!"

Criminal Minds' Paget Brewster: Prentiss and Hotch will have a "nice little moment"

That's mostly because Cook herself is active in real life and loves "being physical and working out." In fact, she surprised the show's stunt coordinator, Tom Elliott, with her skills during training. "Tom didn't know that I was a physical person — that I can do a roundhouse kick, so we incorporated that in. It was fun because he was discovering stuff that I can do that he didn't know," she says. "We just sort of started choreographing this dance, I guess you can say. It was a lot of fun — a really creative process. ... On the day of, when we were all costumed up, it was awesome. We actually got some really great behind-the-scenes footage that I think the fans should keep an eye out for — we walk through the stunt process and they filmed me getting the beat-up makeup on."As with any good fight, JJ will have some bruises and blood to show for it, but Cook emerged from the stunt injury-free. "I'm a pro! Not bad for my first one, huh?" she says. "We did have one close call. There's a knife involved and thank goodness it was a dummy knife! It was my own fault because I hesitated for a split second. It could've been a lot more ugly had it been a real knife, but there have been some gnarly stories, even with prop knives, so I was lucky."After the final punch is thrown, Cook just hopes that fans will see JJ differently — or at least more than just the sympathetic nurturer of the BAU.

Watch clips from Criminal Minds

"I think her being a mother, there's always going to be that 'mother hen' nature about her," she says. "JJ's still going to juggle being a mom and being an agent, and she's still going to listen to victims, but this episode, you'll see how tough she is. She holds her own. She is a tough, butt-kicking cookie. She's come a long way from the girl who was scared of the dogs! It's a very revealing episode."In that vein, the episode will also reveal an "interesting" relationship between JJ and another member of the team. Don't worry — it's nothing romantic (JJ's still with Will [Josh Stewart]), but it is "eye-opening," Cook says. "Let's just say it will fill in the blanks a little bit more as to what she had been doing the past year."And now that she's got her first brawl underneath her belt, when will the next one be? "I have no idea, but I hope soon," Cook says. "I have to start all over again and ask!" Criminal Minds airs Wednesdays at 9/8c on CBS.