After a couple weeks off, NBC’s ‘Grimm’ returned last week with not one but two new episodes, on Thursday and Friday respectively. (The Thursday ep filled the time slot for ‘Prime Suspect’, which is unfortunately on the verge of cancellation.) The first of the two episodes puts a new spin on the fairy tale of the Pied Piper.

‘Danse Macabre’ opens with the murder of a college music professor disliked by his students for pushing them too hard. After one particularly abusive rehearsal, he gets into his car and is swarmed by rats. It seems a little silly that he isn’t able to just get out of the car, but we’re told later that he had a heart attack from fear. It also seems a little silly that he wouldn’t notice the hundreds of rats in the back seat of his car before getting in it. Anyway, by the time his body is discovered the next morning, it’s been chewed up real good. The gore effect is pretty grisly, and the episode spends a lot of time lingering on it.

Nick and Hank investigate. The professor’s students (mostly a bunch of entitled rich kids) point them in the direction of a boy named Roddy Geiger, who had recently been suspended from school for fighting and is the son of a rat exterminator. That’s motive and opportunity. Unlike the other kids, Roddy isn’t rich. He and his father live in a trailer under a bridge. However, Roddy’s an amazing violin prodigy with a talent for mesmerizing rats with his playing. That’s probably because Roddy and his father are reinegen – in other words, rat people. (The father claims that he sets the rats he captures free on a mountain.) They’re the lowest caste in the creature kingdom. Nobody wants anything to do with them.

By night, Roddy is also secretly a popular DJ called Retched Kat, who wears a big cat mask when he plays the rave scene. None of the rich kids who are fans of Retched Kat know that he’s really Roddy, of course.

Naturally, Roddy isn’t the killer. He’d been having a secret star-crossed relationship with a rich girl. Her boyfriend set it up so that he’d be suspended. A group of the rich kids together put the rats in the professor’s car and framed Roddy. They claim that they were just trying to scare the teacher, but don’t exactly seem heartbroken that he died.

When Roddy puts all the pieces together, Retched Kat sends all the rich kids a text invite to a hot new rave in the basement of an abandoned building. He lures them there with his music, kind of like the Pied Piper, get it? Once they’re trapped inside, he begins playing his violin, which brings on a big rat attack. The kids freak out, but fortunately Nick gets there in time to break it up by firing off a few shots and scaring the rats away. The real killers get arrested, and Nick lets Roddy slide on the whole attempted murder thing.

In a related story, Nick’s refrigerator breaks. The repair man happens to be a reinegen, who panics when he realizes that Nick is a Grimm, and almost tells Nick’s wife about his secret career.

‘Danse Macabre’ is a decent episode. The premise is a fairly clever updating of the Pied Piper story, even if some of the plot details (like Nick just letting Roddy go) don’t hold up to scrutiny. Amusingly, the location of the first rave party looks just like The Bronze from ‘Buffy’. I’m sure that was intentional.