Grimm took a walk on the Fringe side tonight with "Of Mouse and Man," a serial-heavy episode.

It’s a fine line to walk, between serial and procedural, and leaning to one side or the other can be a scary proposition. How much is too much? Will the audience like it? Pushing the story ahead too quickly could alienate them. Not pushing it enough results in an audience that can grow disinterested.

That’s a lot to worry about, and yet I had none. “Of Mouse and Man” was a fantastic episode.

Yes, there were still procedural elements to be found. Marty, who was trying to get over years of emotional pain from his finally dead father could never truly escape him. Marty saw anyone who looked down on him as the face of his father. It’s a nice change of pace to, while not actively root for a villain, feel some sympathy and compassion.

Marty dealt with all of it the best way he knew how: going to his safe place. Which meant surrounding himself with plenty of junk to provide a buffer and cushion to the difficulties of life. Eventually, not even that became enough to cope, and the demons his father left him pointed him to murder.

The serial elements come into focus with the other two story threads: Eddie and Juliette. Beginning with Juliette, while she isn’t necessarily suspicious of Nick (yet), she is suspicious of the people taking pictures of her house. I might upgrade her title yet again for being so proactive and tracking these people down after Nick got their address from the plates she wrote down for him.

The Oblingers think she’s dangerous, maybe even a Grimm, but Juliette is so far out of the loop in this scenario it’s almost not even fair. Mainly because she doesn’t suspect Nick, and I wish her suspicions were piqued towards him. I’m having a hard time believing, other than being blinded by love and job hazard, that she’s not curious about all of these recent developments. For now though, I’m willing to let it go though because she’s finally getting to do something other than the super spoon.

As for Eddie, he didn’t have much to do this week, but his scenes certainly left an impact, particularly the ending scene. We all know Eddie and Nick are friends and have a bond, but it doesn’t even look like outside forces can come between them. Eddie was beaten to a bloody pulp and a scythe was written in his own blood on the hood of his car. Yet he’s still willing to help Nick, even if that means going against the reapers.

Speaking of reapers, it’s about time we finally know what one of their goals is: status quo. They don’t want Grimms and Creatures having friendships and beer together. They want the eternal struggle of kill or be killed to continue. Which begs the question: did Renard order this? Why is he not willing to kill Nick, but may be willing to almost kill Eddie?

Hopefully Grimm will teeter every once in a while towards a heavier serialization because “Mouse and Man” really is one of the best episodes of the season.