'Dancing With the Stars' recap, semifinals results

The judges pick an encore, but given the way the stage is set up, it's clear the audience knows what the routine will be. Judging from the screams, it must be William -- and it is. The white pants of infinite tightness are BACK, baby. This is not the same routine that got a 30 last night -- William's pants are whole-assing it, but he's only half-assing this dance.

Footage from last night -- the judges seem very disappointed for Katherine that she had the injury that caused the flub at the end of the routine. Katherine keeps apologizing to Mark. We go straight to results and they're safe. From the way she's jumping around the stage, her back seems pretty good. Or joy makes her feel no pain. Tom reminds us they were the lowest scoring couple, so who knows who will go home now?

And now it's the discuss-the-competitors montage -- Maria's weakness is her injuries. William's biggest weakness, per Mark, is his technique. Katherine's strength is her grace and her legs. Mark says her biggest weakness is her own mind, "psyching herself out." Mark says that Donald's looking like he's leading Peta, but Peta says that his stiffness is a liability. Cheryl thinks Donald may not have peaked yet.

Up in the skybox, Brooke is showing Mark and Katherine a slowed-down clip of the flub at the end of the routine. They're trying to figure out what went wrong; Mark not getting the full rotation on his movie might have been to blame, but I don't know how that jibes with a back spasm. Sometimes things just happen.

We find out that Tristan and Chelsie are the pros chosen for the Design-a-Dance -- it's a samba to Beyonce's "The End of Time." We see rehearsal footage before they perform and they're both kind of adorable. It's fun to watch the pros dance with the pros and you can tell they enjoy getting to go flat out like that.

Now we get a performance from Alanis Morissette singing her new single, "Guardian." It may be new, but it doesn't sound it, with the pseudo-grunge guitar opening. I'm a little bored by the song in this setting, although I might like it on its own. I keep getting distracted thinking about how Alanis used to be engaged to Ryan Reynolds. Remember that?

Footage from last night for Maria and Derek -- Maria licks her hand and smooths down Cheryl's hair. That's both gross and adorable. Backstage Derek warns Maria not to scream and she's soooo good until she realizes she's in first place. They're in jeopardy. Shocker! But not really, after Katherine was pronounced safe.

And now we get a performance featuring Julianne Hough to promote "Rock of Ages." That movie looks both terrible and terribly entertaining. Oh, interesting -- that was choreographed by Mia Michaels, who'll you know for sure if you watched "So You Think You Can Dance." Tom asks Julianne how "that boyfriend" is treating her and when she says "well," he gives her the cutest fatherly squeeze. I still love Tom.

Carrie Underwood performs. She's not my thing, but people who like her probably liked this, so good for them.

William and Cheryl's footage from last night shows William's son completely sacked out on his mother's lap -- so adorable. I'd like his chances in a cute-off against Donald's adorable kids. Cheryl clearly had some sort of wardrobe malfunction that I didn't even notice last night. William points out that his mom was out in the audience and Cheryl thanks her for "making" that bum of his.

Donald's prompted in the backstage interview to answer the question, "Does he want to be in the finals?" His "hell yes! What kind of question is that?" delivery is hilarious.

Results: William and Cheryl are safe. Donald and Peta are in jeopardy.

One of the featured tweets onscreen says that if Maria and Derek go home tonight, the tweeter will lift up his/her TV and throw it against the wall "Hulk" style. Oh dear. Have a hot cocoa and settle down.

So it's down to Maria & Derek and Donald & Peta. I've grown to really like Maria, but I'm Team Donald all the way. Tom echoes my sentiments when he says, "No matter which way this goes, it's gonna suck."

And Maria and Derek are going home. There are boos in the ballroom -- it is kind of crappy to go home the night after you were only one point off perfect for the night.