It's Decades Night on Dancing with the Stars- and also Night 1 of the show's10th anniversary shindig, which continues tomorrow with a special hour that will spotlight alums of the show.

But tonight, of course, is all about the current competition. A few housekeeping items to take care of before the dances get underway:

-Sasha Farber is standing in for an injured Derek Hough to dance with Nastia Liukin this week.

Derek Hough: Injuries are "incredibly frustrating"

-The double elimination that was heavily teased last week has been pushed to next week, and the couple that ends tonight with the highest score is granted immunity.

-The couples without immunity will enter a dance-off at the end of the night to get extra points.

With that out of the way, on with the show!

Riker Lynch and Allison Holker (1920s quickstep)
The dance: Riker and Allison's baseball-themed routine is cute, and Allison's observation during rehearsals that this is the perfect dance for Riker holds true. He doesn't miss a beat, and brings a youthful energy to the old-school jazz number (even though his facial expressions are a little too forced at times). For my money, Riker is also the contestant that consistently improves the most week to week.
What the judges say: Len said Riker hit a home run with the dance (but will he fulfill Riker's dream of handing out his first 10 of the season?). Julianne has a few minor notes on Riker's frame. Bruno calls the tap section "brilliant" but says Riker is sometimes too tight in hold, which Carrie Ann seconds.
Score: 37 (out of 40)

Chris Soules and Witney Carson (1940s foxtrot)
The dance: Maybe I'm just suffering from a little Monday lethargy, but while there are a few peaks in this dance, it mostly just flatlines. Chris' lack of charisma doesn't do any favors to a dance that's a little boring to begin with, though his footwork is definitely improving week after week. Also, what was the strange moment after the dance where the camera stayed trained on the audience as Tom Bergeron was begging, "Chris, come back!"?
What the judges say: Julianne says the dance and production were "awesome." Bruno loves Chris in a sailor uniform and quips that he's turning ... into a dancer. Carrie Ann tells Chris he's the underdog but has suddenly become the "one to watch." Len says his hold needs to be polished a bit.
Score: 31

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Rumer Willis and Val Chmerkovskiy (1960s jive)
The dance: Yikes. That neck-snap Rumer suffered Sunday night in rehearsals looked super painful. I have to wonder how Rumer and Val feel, having to take the stage after that wince-worthy rehearsal footage. They don't seem to be any worse for it - either that or Rumer is a great fake-smiler. Their jive is fun and frothy - not the pair's most intense number, but good nonetheless.
What the judges say: Bruno likes the character Rumer played but gives her a minor note on her hands. Carrie Ann thought the dance was "pristine," but was too safe to capture Rumer's full essence. Len critiques Val more than Rumer and said the routine could have used more flair. Julianne gives Rumer a pep talk.
Score: 35

Noah Galloway and Sharna Burgess (1970s jazz)
The dance: Oof, the footage of Noah and Sharna from last week is so awkward. Luckily, fellow amputee (and former Dancing finalist) Amy Purdy showing up to coach Noah is a little more uplifting. But this dance lacks a little content - for the first half of the dance, I feel like Noah's barely moving (and what he is moving isn't his feet). Points for the costumes, but the rest of the dance is just not great.
What the judges say: Carrie Ann loses her sh--. "What was that?!" She gushes, standing up. (Were we watching the same dance?) Len says Noah is "twice the man" as some people with double his limbs, but notes that the backup dancers were too distracting. Julianne says it's the most fun she's ever had on the show, and Bruno says the dance was the perfect combination of hot and cold.
Score: 36

Robert Herjavec and Kym Johnson (1980s Argentine tango)
The dance: Robert and Kym show us the more sultry side of their showmance, which mostly works. Robert's steps aren't as precise as they should be for the tango, and I actually cringed during the lift when Kym smacked him in the face with her crotch. Save something for the bedroom, guys! Pretty sure everyone in the audience needs to take a cold shower after this.
What the judges say: Len compares Robert's dancing to Chutes & Ladders, but says this was an up week. Julianne praises Robert's timing and enjoyed seeing a different side of him. Bruno basically says it was obvious how horny Robert is for Kym. Carrie Ann appreciated their chemistry, but believes Kym was "too much woman" for a shell-shocked Robert at times.
Score: 31

Nastia Liukin and Derek Hough Sasha Farber (modern Charleston)
The dance: We finally get video footage of Derek's injury, which occurred just a couple of hours after last week's show. Suffering from a broken toe and a sprained ankle (OW), Derek still choreographed this routine but has to sit out the dance (or sit in the dance, as it were, thanks to a clever bit of choreography). The subway motif is brilliant, especially given Derek's cross-coastal trajectory thus far this season. And Sasha's a more-than-adequate stand-in (even if Derek does still steal the spotlight by singing towards the end of the routine). Best routine of the night so far!
What the judges say: Julianne says they "killed" it, and Bruno is equally blown away. Carrie Ann leaves the table and gives Nastia a hug for finally shedding her gymnastics tendencies. Len's critique is reduced to just a thumbs up, for time.
Score: 38

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Willow Shields and Mark Ballas (futuristic jazz)
The dance: Dancing really saved the best for last tonight. Mark and Willow's "Ninjazz" (groan) is just as good as, if not better than, Derek and Nastia's routine. The production on this is amazing, incorporating a nice springtime nod to Japanese cherry blossoms, and a brilliant camera angle that shows Willow and Mark appearing to float through clouds at one point. Oh, and as a side note, the dancing is great too, especially that eye-popping lift!
What the judges say: Bruno calls the dance "hypnotic." Carrie Ann gives the first part of her critique in Japanese, which no one understands, but then says the dance lacked a little energy in parts. Len compliments Mark's creativity, and Julianne disagrees with Carrie Ann, saying sometimes smaller movements are better.
Score: 37

Now it's time for the dance-off, through which the winning couple can get two extra points. The match-ups - as selected by the higher-scoring pair, with the lower-scoring pair selecting the dance - are as follows:

-Riker/Allison vs. Mark/Willow (salsa)
The dances: Riker and Allison's salsa is more sensual than Willow and Mark's (thankfully), but also seems just slightly less fluid. Willow and Mark's routine is buoyed by Mark's gyrating hips. (An observation from my colleague Robyn Ross: "Willow literally went through puberty just now.")
What the judges say: Nothing of substance, other than noting that the routines were very different but the competition is close. But they unanimously vote for Willow and Mark.
Who won? Willow and Mark (4-0)

-Noah/Sharna vs. Robert/Kym (cha cha)
The dances: Noah and Sharna fall out of sync early on in their dance, and Noah's confidence never seems to recover. (It's not unlike what we saw last week after he got flustered.) But lucky for them, Robert and Kym aren't much better. Robert makes a couple of egregious errors towards the start of the dance, and though they later get back on track, it's far from perfect. It's telling that Sharna asks the judges if they can just tie.
What the judges say: Julianne notes a "minor mishap," but it's not clear who she's referring to. Carrie Ann said one dance was tight but lacked content, and one was mistake-filled with a lot of content and fun. Len mostly just shrugs.
Who won? Noah and Sharna (Len and Julianne vote for Noah and Sharna; Bruno and Carrie Ann vote for Robert and Kym, with Len's being the deciding vote)

-Rumer/Val vs. Chris/Witney (foxtrot)
The dances: No contest. Rumer and Val are nearly flawless as always, and this feels like it could be their main routine for the week, rather than an afterthought. It's dramatic and elegant and hits all the right notes. Chris, on the other hand, looks like a deer in headlights from the get-go, up against one of the two couples he specifically said he didn't want to go head-to-head with (the other being Riker and Allison). The dance isn't bad, per se, but the lack of charisma comes back to haunt Chris again.
What the judges say: All the judges praise both couples, but Carrie Ann notes that there was one dance that was "hands down" above the other and Len tells Chris he's just unlucky. Poor Chris.
Who won? Rumer and Val (4-0)

Dancing's Derek Hough may miss the rest of the season

Now it's time for the results and elimination.

Safe: Noah and Sharna, Robert and Kym, Chris and Witney, Riker and Allison

In jeopardy: Rumer and Val, Willow and Mark

Eliminated: Willow and Mark. A shame after their stunning number tonight!

What did you think, Dancing fans? What was your favorite routine of the night? Were you disappointed to see Willow and Mark go home? And what are you looking forward to on Tuesday's anniversary special? Sound off in the comments!

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