Warning: This review contains full spoilers for Rick and Morty Season 9, Episode 5!

I'm of the mind that Rick and Morty should reference past episodes and storylines more often than it does, so theoretically, I should be all over "Jer Bud." This episode is basically a sequel to Season 1's "Lawnmower Dog," finally bringing Morty's (Harry Belden) old dog Snowball (Rob Paulsen) back into the fray after years' worth of visual cameos and Easter eggs. But instead of being a fun callback to a simpler and more innocent time for the series, "Jer Bud" merely argues that Snowball was better left in the past.

Sometimes the series struggles to take a fun premise and build on it in a meaningful way. Episode 5 is different in that it never really seems to have anything worth building on in the first place with the Morty/Snowball storyline. It starts off a little bland, and it never gets off the ground when Morty finds himself dragged into another conflict involving the fate of an alien civilization.

In this case, Morty finds himself unwillingly thrust into the role of liberator of a race of grotesque, inbred humanoid pets called Mups. This episode leans a lot on the idea that, once they're granted sentience and given power over their own destinies, dogs wind up behaving an awful lot like humans. And sure, that tracks, but there's never much humor to be found in the whole situation. The concept of the Mups is never particularly funny, nor is there much visual humor to their physical deformations. None of it clicks as it should.

The one thing I'll grant this storyline is that at least it makes an effort to shuffle Rick (Ian Cardoni) to the background and allow Morty to shine on his own. Rick has such a tendency to dominate the series from week to week, so it's nice to see a concerted effort to shift the spotlight to the rest of the Smith family. It's just too bad that Morty's storyline is so underwhelming.

Thankfully, at least we can usually count on Jerry (Chris Parnell) to salvage the show in its weaker moments. The Worm Jerry subplot is far more successful than the Morty/Snowball storyline. Not unlike in Episode 4, the show gets a lot of mileage out of the fact that Jerry is possessed by a larger force and acting a bit out of character. It's a lot of fun watching the worms inside Jerry push a simple job interview to bizarre and inane heights. Parnell is clearly having a blast exploring this different, much cooler side of his chronic loser character.

The Worm Jerry storyline takes a lot of amusing twists and turns by the end, spanning from a seedy alien drug den to a plane falling through the sky while Jerry cooly guides a woman through childbirth. This storyline makes solid use of the supporting characters around Jerry, including Rick himself and both versions of Beth (Sarah Chalke). Season 9 hasn't done much with Beth or Summer (Spencer Grammer) yet, so it's good that at least one of them gets a bit more attention here.

The two halves of this episode are wildly opposed in terms of quality, and ultimately they sort of cancel each other out. The result is definitely the weakest installment of Season 9 overall. But hey, take solace knowing that it only gets better from here in the latter half of the season.