10/10/2013 03:43 pm ET Updated Jan 23, 2014

SVU Goes Undercover to Catch Rapist Cops

Olivia's in love! Munch is retiring! And Cassidy reluctantly kisses three women in a single episode. "Internal Affairs" was a smart riff on some seriously troubling headlines -- but it was the personal drama that stole tonight's show.

Recap: A terrible NYPD cop named West is escorting drunken young women home from nightclubs, only to rape them once they're inside. West's female partner, Quinn, routinely stands guard, lies to protect him, and makes bogus 911 calls for cover.

Beady-eyed Lt. Tucker of Internal Affairs enlists the help of SVU and Olivia's on-again boyfriend, Cassidy. Tucker promises to return Cassidy's badge and close the investigation into Cassidy's own IAB case if Cassidy goes undercover and catches the bad cops.

Cassidy agrees, takes a break from adorably unpacking wine glasses into the new apartment he and Olivia are moving into, and becomes West's new "partner." Along the way, Cassidy has to hook up with a call girl in order to gain West's trust. Poor Olivia, who is Cassidy's backup, has to listen to her boyfriend murmuring, "Oh yeah baby, right there" to a hooker, via his hidden microphone.

As I recall, Cassidy got into quite a heap of trouble last season for doing exactly this. The man is cute, but he is not a fast learner.

Amanda hasn't had an opportunity to wear spandex in a while, so they dress her up as a sexy drunk-and-disorderly nightclubber, who West immediately escorts home and starts to fondle. Cassidy also takes a turn, to keep West's trust. But before anyone can get to second base, West gets a call and learns that Cassidy is undercover. West and Quinn kidnap Cassidy and prepare to shoot him on a loading dock! But our good SVU detectives arrive in the nick of time and haul the dirty cops away. Phew.

In the interrogation room, Olivia asks Quinn why she covered for West all these years. "You love him, don't you? You're forty years old, wondering if you'll ever have a family -- or if riding around with him will be enough for the rest of your life. Did you really think he'd leave his wife and kids for you? You spent the last five years hoping he'd suddenly turn and realize you're the woman he can't live without."

Of course, Olivia is describing her own relationship with Elliott. And the truth of it hits her almost as hard as Quinn, who cries and confesses.

Olivia finally gets to go home and have that glass of wine with her new live-in lover. Cassidy kinda fumbles his explanation about the hooker, but holds Olivia so tenderly that all is forgiven.

Verdict: B+

What they got right:

The plot was ripped from the headlines of an appalling real case. Two NYPD cops were accused of escorting a petite young fashion designer home after a night of drinking. Kenneth Moreno was charged with raping her while Franklin Mata was charged with being an accessory to rape, for acting as a lookout. The woman testified that after the officers escorted her home, she passed out only to awake to being raped. Moreno admitted "spooning" her in her bed and making bogus 911 calls to cover for the numerous times he returned to her apartment. The cops were acquitted of rape charges, but convicted of official misconduct. The woman sued the city.

This episode accurately captured many of the challenges of prosecuting a case like this: credibility issues, the "thin blue line" of officer's protecting each other, and the difficulty of cobbling together a story with a witness who can't remember everything that happened on the night in question. Olivia's efforts to get the victim to trust her and talk, despite intimidation and fear, was well done and rang true.

What they got wrong:

Cassidy was the worst possible choice to be the undercover cop here. Sending in a UC, you want someone who is going to have impeccable credibility, because he'll likely have to testify about everything later at trial. But Cassidy himself was in trouble with IAB. And when Tucker promised his badge back, he handed West his defense on a silver platter. Imagine the cross-examination: "You lied about what you saw, didn't you, Officer Cassidy, in order to get your job back?"

It was ridiculous for Quinn to be a woman. A male cop would do this for terrible but obvious reasons. But Quinn does it to protect her serial-rapist colleague because she's in love with him? I've seen some serious cases of falling for bad boys, but this was too much. Chalk up another example of SVU making the perp a woman whenever humanly possible (and sometimes even when it's not).

What do you think, SVU fans? Leave your comments!