Double the Kenzi — that’s a recipe for success, right? But it’s not just a gimmick to get us into the story, it’s one of the more intense episodes of

The discovery that “Kenzi” isn’t really Kenzi has Bo determined to do whatever it takes to rescue her best friend, but in trying to get Trick’s help, she inadvertently reveals her role in the recent succubus killings, forcing Dyson and Tamsin to do their duty as police officers. The fake Kenzi continues trying to make inroads with the others, but Bo winds up receiving help from an unlikely source as the real Kenzi resists her kidnapper and tries to escape her captivity.

There’s not a freak-of-the-week or the typical procedural A-story to be seen in “The Kenzi Scale”. Instead, we pick up right where the previous episode left off, and things spiral out of control from there. It’s a very welcome departure from the typical formula of Lost Girl, and for the first time in a long time we get a plot that directly involves our protagonists and their fates. What’s also surprising is how directly “The Kenzi Scale” ties in the other major plotline of the third season, that being Bo’s killings, and makes it integral to how the episode plays out.

Double the Kenzi is fantastic, especially because one of these Kenzis is the villain of the piece and a chance for Ksenia Solo to continue stretching her acting muscles. The script does a great job of setting up a truly unhinged villain, but it’s the performance that brings out the neediness and the psychopathy. You wouldn’t think a tiny Goth girl could be terrifying, but she is, and she only gets more terrifying as the episode unfolds and we see what she does to Bo, Kenzi and eventually Dyson. She creates a real desperation and the opportunity for a lot of tense moments, and it makes for compelling TV.

Despite Kenzi’s double-act, she doesn’t dominate the whole episode and there’s plenty of material for Bo and for Anna Silk. The importance of the Bo/Kenzi dynamic is touched on again for its ability to keep things light and fun and normal in the face of supernatural weirdness. She gets to team up with Tamsin for much of the episode, which is also a fun dynamic given the character’s distrust of one another and sets up some character beats in the episode’s tag. And we start getting answers about the mystery surrounding Bo, which looks like it’s the beginning of the season’s next arc.

Like the previous episode, this one builds on the season arcs to great effect and propels the show into new storytelling territory. Unlike the previous episode, there’s no fat or chaff to wade through in order to get to the meat of things, just a solid episode that focuses on the main characters and their struggles. Throw in a lot of great character interplay with dynamics new and old, and sprinkle on an extra Kenzi for good measure, and not only does “The Kenzi Scale” succeed, it matches what had been the best episode of season three so far.

John Keegan is Editor-in-Chief for Critical Myth, a partner site of SciFi Vision.  Paul Pearson is Critical Myth's reviewer for Lost Girl.