"The Thirteenth Step" was a grisly, intense and disturbing episode of Criminal Minds, even by the high standards set by the CBS procedural in each of those categories.

What could have been a cliched plot - law-breaking, madly-in-love couple on the run from the world - was uniquely done and well-executed, however. Not to mention frightening.

Perpetrators Sydney and Ray are both in AA, but they've already broken "The Thirteenth Step," an unwritten rule for not becoming romantically involved early in sobriety.

The consequences proved fatal for anyone in the Midwest who got in their way.

To the extent that two guest stars can make an episode, Adrianne Palicki (Friday Night Lights' Tyra) and Jonathan Tucker (The Black Donnelleys) did so as Sydney and Ray.

Both were terrific as the troubled couple “working the steps” in a murderous, drunken spree so terrifying you grew nervous, shaking whenever they came back on screen.

The original, Criminal Minds-style spin on the oft-repeated Bonnie & Clyde saga was AA, and the examination of the couple's past as they took on the hardest steps (7-9).

Suffice it to say, the program didn't turn out as planned for these two.

Bastardizing the 12 steps in haphazard and delightfully devious (for them) ways, the twosome stole the show this week, commanding our attention much more than the BAU.

Palicki, who we loved on FNL and the unfortunately-axed Lone Star, showed real versatility, innocently toying with her candy ring-pop one minute, bashing heads in the next.

This show can be over-the-top melodramatic at times, but this week it felt anything but. Seen through the eyes of these crazed companions, the violence served a purpose.

From the moment we met Ray at his AA meeting, you knew it was going to go horribly wrong. Shooting up the entire room was just the beginning of their downward spiral.

The grip of addiction is stronger than people realize, and Reid's observation that they were "working" on 7-9 gave the team an insight into the twosome they were tailing.

Having become completely unhinged, Ray and Sydney turned the AA principles around by trying to force people - their abusive parents, namely - to make amends to them.

When they're eventually cornered, Morgan uses psychology to turn them against each other, and fittingly for this episode, the climactic scene was as frightening as it gets.

After freeing the hostage, Ray lays Sydney down in the store, kissing her with passion, with the kind of false elation they'd shown all night. Then he chokes her to death.

"The Thirteenth Step" practically gave me nightmares, a testament to how harrowing and real the characters seemed, despite the bizarre, made-for-TV circumstances.

In the night's brief subplot, Prentiss meets Sean McAllister, who had been trying to track her down. He tells her that Ian Doyle has vanished from prison. He’s off the grid.

Emily asks if he’s headed there and if she’s in danger. Sean says they all are. Presumably this blast from the past will be revisited. Think the show will kill off Prentiss?

Also, Reid and Seaver ... anyone see the connection there?

What did you think of last night's Criminal Minds? What moments stood out to you the most? Share your thoughts by leaving comments below.

Steve Marsi is the Managing Editor of TV Fanatic. Follow him on Google+ or email him here.