'Dancing With the Stars' mixes up the dance partners in Week 5

LOS ANGELES -- Switch-up week is here! It's a week-long crash course with each celebrity meeting a new pro dancer in rehearsal and learning a routine that has them competing against their "old" partner.

What's even better this week? Maks is back! Filling in at the judges table, we see the return of Maksim Chmerkovskiy, who said he planned to be himself, and say whatever was on his mind. Good luck, everybody!

Here's a rundown of the scores, from highest to lowest:

ALEXA PENAVEGA - 40 out of 40

The first perfect score of the season! It seems like this might have been the perfect storm for Alexa. She had a rough dance last week, having a rough post-game with her partner Mark Ballas, and then her switch-up comes into the room - it's Derek Hough! She is beyond excited to tackle the Tango with him. Derek lets her know she should use the mess-up last week as inspiration. Alexa's confidence builds and she says she has a new perspective about dancing now. The studio audience is on its feet, and so is judge Carrie Ann Inaba. Julianne Hough was happy to see this authentic, raw, rough vixen version of Alexa. Bruno Tonioli said he saw a complete metamorphosis, and guest judge Maks praised her for getting out of her head and letting herself shine like the leading lady she is.

CARLOS PENAVEGA - 39 out of 40

Carlos is one determined dude this week. He's gets Lindsay Arnold with his reassignment and she promises him a challenging Quickstep. There's a lot of banter in rehearsal, since Lindsay and original partner Witney are BFF's, but you can tell they put a lot of time and effort into this routine. The judges were blown away, with Bruno calling it "turbo-charged." Julianne Hough thought they owned the ballroom, and Carrie Ann praised Lindsay for her choreography, saying it doesn't get any better than that. Maks said the dance wasn't great...it was amazing!

BINDI IRWIN - 37 out of 40

I think any of the pro dancers would have been thrilled to get Bindi as their partner. You just want to hug her, right? Val Chmerkovskiy connected with her right away, but still wanted to challenge her to go even further with her newly-found dance skills. Val says this is the toughest Cha-Cha he's ever choreographed. Bindi brought some of her life into rehearsal one day in the form of a python. I'm quite sure that's a first for Val! Maks loved the dance and loves Bindi's positivity. Bruno said she is the essence of joy, with precise footwork to boot. Julianne called her a ray of sunshine, and Carrie Ann said they took the dance to another level.

ANDY GRAMMER - 36 out of 40

New partner Sharna Burgess seems determined to have Andy show his sexy side. She knows it's in there, and she choreographs an Argentine Tango to prove it. Andy is finally realizing he does kind of want to do well in this competition and commits a bit more to rehearsal and his performance. Julianne thought he nailed both the footwork and the musicality. Maks said the performance value was over the top. Bruno told the couple they were steamier than an erupting volcano, and Carrie Ann called it HOT!

NICK CARTER - 35 out of 40

Does Witney know about Nick's group "The Backstreet Boys"? Sure! Her Mom used to listen to them all the time! The biggest thing on Witney's shoulders is Nick's momentum. He's been doing well and she doesn't what to spoil what Sharna has started. They have the Paso Doble, which allows Nick to take the lead a bit with his younger partner. It's a fierce dance, almost too fierce. The judges all thought there was a little too much rock and roll, too much commitment and not enough shape and steps.

HAYES GRIER - 30 out of 40

Allison Holker steps in for the week and teaches Hayes a Viennese Waltz. She takes on the role of "Dance Mom" with him and choreographs a routine that aims to show his youthful but sophisticated side. We also learn Hayes voice is changing...adorable. Bruno thought Hayes looked like the ideal Prince Charming but also seemed a little "kangaroo-ish" and Maks agreed. The female judges liked the dance more, with Carrie Ann asking young Hayes not to grow up too fast.

ALEK SKARLATOS - 29 out of 40

Chemistry with Alek and Emma Slater? Oh yeah. There's a definite like, maybe even lust, connection here. He kept getting distracted during rehearsal and would even get the giggles. Alek said she's so hot, he can't keep his cool. Awww! They have the Rumba so the duo need to play up their steamy sides. The judges praised their chemical connection, but want to see Alek show more emotion. Maks called him the season's dark horse.

TAMAR BRAXTON - 29 out of 40

Louis van Amstel was excited to get Tamar for his switch-up partner. He said he's been keeping his choreography on the simple side for Paula Deen, and he planned to push Tamar to the limit. She worked harder than ever on the sexy Samba that was easily her toughest routine to date. The judges agreed that the compressed time schedule did not do the couple any favors. They were praised for their work individually, but knocked when they were in hold.

PAULA DEEN - 26 out of 30

Like Red Riding Hood meeting the Big Bad Wolf, Paula is a little scared, and a little excited, to dance with Mark Ballas. She loves and fears that he's "edgy" and worries he'll get frustrated with her. He shows off his giant "patience" tattoo. Once rehearsal begins, though, Mark discovers Paula is really a "Bad Grandma" and they look like they have a great time. Carrie Ann and Julianne both thought this was her best dance to date. Maks thought it was fun, but a little safe.

No one is eliminated this week. The judge's scores from last week will be combined with this week's scores, plus the viewer's votes, to determine who gets sent home next Monday.

And we're hopelessly devoted to next week's guest judge: Olivia Newton-John!