Mouse P.I. is occupying a similar place that Cuphead did at its release — a game built on a traditional gameplay genre, but using a very impressive art style and animation to elevate. Both games use rubber-hose animation to deliver the feeling of playing a cartoon, but having gone through both, Mouse P.I. is a massive letdown and a case where the art writes a check that the gameplay can’t cover and is a good study in a failure of worldbuilding and game design.
Peppering it On
Our story stars Jack Pepper P.I., in a gritty noir world where mice run everything, cheese is both currency and drugs, and gangsters, corrupt politicians, and even evil cults, are causing trouble. Like any good detective story, the case starts simple enough with a missing person but soon elevates to a conspiracy that threatens everyone.
Each level has you explore a gorgeously animated and looking world fighting baddies, collecting clues, and rarely, getting new powers. The games arsenal includes pistols, shotguns, an acid gun, a literal cannon, and more; with weapon upgrades available once you get past stage 3.
The combat loop itself is focused on moving from arena-to-arena, with small groups of enemies in-between. Every weapon, to be honest, felt horrible to use without upgrades. Each upgrade not only raises damage, but gives more ammo, reduces recoil, and improves the accuracy.

The upgrade paths are very simple, but radically transform each weapon. (source: Steam)
From time-to-time, the game will embrace the cartoon-nature of the world for set-pieces and consumable power-ups.
Eat a can of spinach, you get Popeye anchor arms to punch everyone around for example. Movement tech is introduced brilliantly by having Jack learn that the physics of his world are a bit malleable, and he can soon double jump, wall-run, and more.
These power-ups and abilities show that there is more under the surface of this world, but it’s time to talk about why this game fails to connect the dots between whimsy and worldbuilding.
To Toon or Not to Toon?
Mouse P.I. tries to present itself as a game heavily inspired by noir, but also a loving homage to early cartoons and animation, but it’s trying to have its cake and eat it too, except there’s no cake. To go into more detail about this, I need to get into spoiler territory for the game.
Spoiler Warning:
The beginning of the game paints this as a cartoon world but still operates under a set of semi-realistic rules. However, there are cracks to this that start to appear that make it seem like there is more toon logic to the world than first appearances would indicate. One of the early witnesses you meet is literally besides herself and is perfectly fine, and no one seems to question why or how.
When Jack starts unlocking new abilities, they are very much in the realm of cartoon logic — spring shoes, tail manipulation, and more. When the cult shows up, more supernatural elements start appearing, including one section that deals with ghosts that again, no one questions or is concerned about the dead coming back.
The only time the game embraces the fact that it’s in a cartoon world is for the asylum level, which leads to the most surrealistic part of the game and is also my favorite level.
End Spoiler
When we take away the art and animation, Mouse P.I. is just a generic shooter that feels like something a AAA studio would have put out in the late 2000’s early 2010’s. The gunplay felt very stilted to me; as someone who has played the recent crop of amazing indie boomer shooters, and it reminded me of the original Bioshocks. The two most dangerous enemies are the machine gunner and sniper ones who can attack you with very little feedback while you’re busy dodging everything else and completely go through your health on hard.

One the biggest wastes in my opinion is this amazing world map. I love the look of it, but it has no real gameplay interaction to it (source: Steam)
Bioshock is a really good comparison, because both games present an amazing-looking world of strange powers and abilities, but only one does anything truly with it from a gameplay point of view.
Fighting Yourself
Whenever there are games that give the player unique abilities or advantages over the enemy, designers have an opportunity to elevate their gameplay by forcing the player to fight one (or both) of these enemy types–
- The enemy who is exactly like the player and can use their own tricks against them
- The enemy designed to counter the player’s abilities, forcing them to adapt on the fly
Former examples include some of the most memorable boss fights in soulslikes — Nobunaga in Nioh, the hunters of Bloodborne, and much more. Latter examples include the marauder from Doom Eternal, and a favorite example of mine from an older game. The Darkness 2 gives the player darkness powers that they can use to overwhelm every enemy they see. At a certain point, the bad guys realize that your weakness is light and start fielding enemies with powered lights to explicitly counter your abilities.
The point is that what elevates these games that make use of original settings and mechanics, is making the world respond to them to challenge the player. Returning to Bioshock, the entire premise of the game is built on the discovery, manufacturing, and selling of plasmids. This becomes a part of the world, with different areas designed around them and advertisements, and the gameplay, with splicers using these plasmids against you. When you battle the big Daddies, it becomes a fight between the player using the plasmids as their advantage vs. an overwhelming brute who does their own thing.
With Mouse P.I. my problem with the game is that the art style is simply there as something to ooh and ah over but has no real bearing on the gameplay outside of a few set pieces. If this is a cartoon world, why aren’t enemies double jumping, wall running and so on? Where is the enemy that is our counter or does their own thing? The toon logic only shows up for specific set pieces… and then it’s gone. The spinach example I mentioned above, that could have been a boss fight or introduce a new enemy type to throw the player off.
The reason why Cuphead was so memorable was that it took this amazing art style and animation and applied it to everything. When a boss transforms into a new form, when you activate one of your ultimate attacks, the fact that even inanimate objects start sneering and attacking the player.
That’s All Folks
It’s been awhile since a game has disappointed me this way. I adore the music, art, and animation of Mouse P.I., but I keep expecting that to turn up more in the gameplay. I know someone will argue that Mouse P.I. is going for homages to noir and animation and not focusing on those aspects. However, an important part of effective world building and game design is that if you introduce something to the world, then it has to become a part of your design. There is still the chance that more of this will show up in the game with the promised first story DLC for it.
Like a pretty dame, the game tried to distract me from repetitive gameplay with an amazing look, but this game design gumshoe was not going to get fooled.
For more of my thoughts on design, be sure to follow me on Bluesky