The second part of Guilty Pleasure Song Night kicks off with a shot of Carrie Ann Inaba falling out of her chair on Monday night’s show — because no one ever gets tired of people toppling over.

Melissa and Tony on “DWTS.” (Adam Taylor/ABC)

Reality star Melissa Rycroft and Tony Dovolani

Dance: Tango

Melissa chooses Britney Spears’s “Toxic” as her guilty pleasure song. We love teenybopper 90s pop as much as anyone, but still — Anyway, Melissa and Tony fret over this week’s routine, since Melissa’s never performed a tango before. Melissa breaks down crying during rehearsal, and Tony wonders out loud if he made the routine too difficult.

(Plus, there’s the whole “Melissa getting whiplash and being taken to the hospital” thing that we saw on Monday’s show, but there’s no mention of that in rehearsal.)

Fortunately, Melissa seems to get the hang of the fast-paced tango by Tuesday’s show — and they win creativity points for Melissa kicking off the dance playing a science experiment coming to life. “I thought you came out and performed that excellently,” Len says, though he adds, “Occasionally I think you could have just snapped a little bit more, but I know you had that problem with your — “

“She was taken off in an ambulance two days ago,” Tom Bergeron helpfully supplies.

“I can only talk about what I see, Tom,” Len snaps. “You keep your witty comments to yourself, and I’ll...”

“Ohhhhhh,” chimes in the audience, who know a good burn when when they hear one.

”That was more of a factual comment in an attempt to find your beating heart!” Tom Bergeron explains, winning us all over.

Scores: 9, 9, 9 for a total of 27 points.

Olympic gymnast Shawn Johnson and Derek Hough

Dance: Rumba

Even though Shawn and Derek have been declared by almost everyone by the almost-certain winners, they’re still nervous about this week. That’s because Gilles is also performing a rumba, and everyone knows he’s the sexiest man alive — or at least, on “DWTS” this season. (For proof, see Carrie Ann falling out of her chair.)

Derek tries to coach Shawn how to show emotion through the sensual dance, though she’s worried that she won’t be able to measure up to the professional actors. Luckily, they’re dancing to Celine Dion’s “My Heart Will Go On,” and who doesn’t instantly get weepy remembering the days when “Titanic” was all the rage?

The duo gracefully glides through the dance, and share a long embrace afterward, with Derek dressed as Jack Dawson from the aforementioned film. “That was awesome!” Bruno yells. Carrie Ann rambles about Shawn showing more maturity, but then chides them for performing a lift. “It wasn’t a was a catch!” Derek and Shawn protest, to no avail. Len, who seems to really have it in for Derek this season, is all cranky and disappointed, saying it wasn’t really a rumba. Carrie Ann and Bruno disagree, but Len’s having none of it.

Scores: 9, 8, 10 for a total of 27 points.

Olympic speed skater Apolo Anton Ohno and Karina Smirnoff

Dance: Samba

Apolo and Karina want to make up for last week’s semi-disastrous hip-hop routine, in which Karina dissolved into tears after tripping during the performance. Therefore, this time, she creates a very difficult routine, and declares it’s going to be their “comeback” week.

Dressed in the shiniest shirt ever made, Apolo spins Karina around on the dance floor, adding a little disco to Rick James’s “Give it To Me Baby” — unfortunately, it’s not too memorable. Carrie Ann isn’t impressed, and says Karina and Apolo need to work on their chemistry. Len, however, thinks it was terrific, though there was “too much thrusting.” Bruno declares it “terriby sexy.”

Scores:8.5, 9.5, 9 for a total of 27 points.

Singer Sabrina Bryan and Louis Vam Amstel

Dance: Waltz

Sabrina, a Disney actress, decides her guilty pleasure song will be “So This is Love” from Disney movie “Cinderella.” Nice corporate synergy! However, Sabrina complains about the slow dance, saying she’s much more in her element with speedier dances.

Dressed as Cinderella herself with Louis as Prince Charming, they twirl around the dance floor, fairy tale-style, though Sabrina looks a bit awkward at times. Len tells Sabrina that this time, Cinderella “going to the ball,” and he enjoyed it. Bruno also loved it, and whips himself into a frenzy, waving his arms around and causing Len to move over to shield himself from poetntial injury. Carrie Ann, on the other hand, didn’t think Sabrina really got the “vulnerability” of the dance, but still thinks it was a gorgeous performance.

Scores: 10, 10, 9.5 for a total of 29.5 points.

Finally, it’s time for Freestyle Team Dance, Take 2: Last night was “Call Me Maybe,” and this time, we get viral video sensation “Gangnam Style” (530 million-plus YouTube views). Tonight, it’s Kelly Monaco/Val, GIlles Marini/Peta, Emmitt Smith/Cheryl and Kirstie Alley/Maks.

Just like the actual “Gangnam Style” video, rehearsal is chaos. “We have no idea what’s going on,” Kelly explains. Gilles and Maks bicker, and Gilles declares Maks the “alpha male,” which makes it impossible for anyone to really take charge.

But there are no trauamtic injuries, like Team “Call Me Maybe,” and the actual dance comes together for the actual performance. Everyone starts out in tuxedos, which they strip off while doing their individual dances. Gilles, in particular, takes it quite seriously, wearing little more than tiny white shorts and a short towel around his waist. No one seems to be particularly in sync with each other, but it’s wildly entertaining.

“That’s the most fun I’ve had in 15 seasons!” Tom Bergeron exclaims, and the judges agree. “That was the greatest number I have ever seen!” gushes Len. Whatever Bruno says is drowned out when Gilles throws him his towel, and immediately runs to hide, since he’s basically in his underwear at this point. The crowd goes crazy. “You guys were a hot mess,” Carrie Ann admits, but still thinks it was “crazy fun insanity.”

Scores for the group dance, which will be added on to the individual couples points: 9, 9, 9 for a total of 27 points.