Sometimes you have to forgive Criminal Minds for the handwavey stuff because the rest of the show it worth it.  The characters it builds tend to be complex, understandably real people that have complicated relationships with each other.

So, we'll forgive Criminal Minds for the hand-wave of Reid and Prentiss being involved in what should be a city or county child abuse investigation, we'll forgive the fact that a girl of 15 is a little long in the tooth for most pedophiles, we'll forgive the BAU for not shutting down the press hard when they realized that there was a leak.  We'll forgive, because in this episode we got some of the most awesome Reid, Prentiss, team, and bad guy we've had in a long time.  

The episode starts with Prentiss and Reid posing as Child Victim Interview Specialists in order to interview the children of a religious group that's sequestered itself on a ranch.  It's ... really unclear why they're there, since it seems more logical to have real clinical psychologists or social workers there.  Then, a reporter calls the ranch to alert them about an incoming raid.

...Yeah they don't clear up why a reporter would call ahead of the raid to alert the compound or why anyone would endanger other people's life by alerting the media beforehand.  And then they let the same reporter that got a policeman, a social worker, and a member of the cult killed hang around so he can continue to report leaked information that endangers everyone inside the compound.

Anyway.  Forgive and forget because Prentiss and Reid immediately begin laying the groundwork to manipulate the situation from the inside.  The BAU shows up as hostage negotiators and one of the strengths of this show is how clearly a team they are.  The agents inside know what the agents outside are going to do, and more than that, they trust them.  Similarly, the agents outside are using bugs to listen and decode messages from Reid and Prentiss.

In this episode, die hard fans will compare the Reid from first season's "Derailed" to the Reid in this episode.  In both episodes, Reid got inside the head of a criminal in order to save hostages.  In both episodes it was by buying into the criminal's fantasies, by making them empathize with Reid.

However, what was fascinating was how Reid has changed from that first season.  In that first season episode, it was so foreign to the other BAU members for Reid to go in to a dangerous situation, that Hotch almost ended the mission before Reid put on his costume.  Similarly, Reid took some dangerous chances and didn't play it by the book.  It wasn't so much that the team didn't trust him, it was more that they saw him as a brilliant intellectual rather than an able agent.

At the end of "Derailed", Elle looked at Reid in shock that he was able to so thoroughly get inside Teddy's head.  There was absolutely no parallel shock in "Minimal Loss." Instead, Prentiss took one look at the situation and knew that she could take a beating, that Reid would be better able to manipulate Cyrus and gave herself up as FBI.

Just as in "Derailed", Reid worked as the inside man because he understood how the criminal thought.  He understood that Cyrus would try to convert him, he understood that through that he could manipulate the man.

At the end of the episode there was none of the shock from "Derailed."  No one was surprised he survived, no one was surprised that he was good at his job.

Another thing to love about this episode was how it inverted well known stereotypes.  In almost any movie or tv show where one of two partners gives themselves up to save their partner, it is inevitably the man who gives himself up to save the woman.  The theory is that a big strong man can take a beating, but a woman can't.  Here, when Cyrus had a gun pointed at Reid, Prentiss gave herself up to save him.

When Cyrus was literally beating the hell out of Prentiss, the violence wasn't glorified in any way: we saw most of how bad it was through the BAU.  While listening, the team clearly wanted to go in, but when Prentiss said that she could "take it," they trusted her.  Big strong men didn't know better than the little lady: she was a full member of the team who understood her own capabilities and limits.

Moreover, even when she was tied up and left alone, she wasn't helpless.  She wasn't sitting waiting to be rescued, and she wasn't artfully covered in blood while wearing a torn blouse.  She looked beaten up, but not powerless.  Her goal was the same as it always had been: to get the women and children out.

Just as Reid was able to read Cyrus, we were able to see Prentiss read other people.  Beaten up and locked in a room, Prentiss was able to communicate with the outside, get the women and children out and still let Morgan know where Reid was.

Despite all the hand-waving, this show will forever rock for that alone.