Mouse P.I. For Hire: All Secret Door Codes In The Depths

The Depths hands over a locked door and a panel of levers with zero explanation, and the eight codes hiding behind it split evenly between real rewards and pure developer indulgence.

Riding the elevator down into The Depths during "Shrewd Shrews" is the kind of scale shift Mouseburg doesn't bother explaining either. One second you're crawling through a shrew community's back alleys, the next you're standing in an underground city big enough to swallow half the campaign's remaining runtime. The locked door sits close to the elevator, and there's no real hint about what's behind it beyond a control panel reading four zeros.

Getting there isn't complicated once you know the route. Off the elevator, take a hard left and keep hugging that side past a frightened local mouse and a wall tagged with "SPIKE-D IS MICE." A small wooden staircase leads up into the room with the panel itself.

The Four Codes That Actually Pay Out

These aren't hidden behind anything resembling a real puzzle. They're scattered as environmental details, the kind of thing that rewards actually looking at a room instead of running through it.

2137 sits underneath the wooden platform right outside the code room itself, scratched into the support beams alongside a couple of loose coins. Punching it in gets a line of Polish dialogue out of Jack Pepper, something about not needing to choose when he can just take both, and the room pays out 10 coins on a table inside.

0451 is a small nod for anyone who's spent time with older immersive sims. It's written on a paper in the back of a storefront called Quick Loans Edek Pitos & Co., across the ground floor near the shrew community. Walking in past the banker and reading that paper gets Jack calling it a classic, which it is. Another 10 coins follow.

1234 takes more legwork. It's up on the second floor near a "Writers untie!" tag, reached by grappling up to a balloon point and then crawling under a platform marked with fish graffiti instead of walking through the nearby door. The warp pipe there spits you into a cramped room with the code scratched on the wall. Jack's response is a joke about it matching his luggage combination, and the room's got spilled drinks along with 10 more coins.

3125 shows up much later, during the stretch where you're chasing the magnet carrying the valve you actually need. Before grabbing the valve off the "lost n' found" desk it lands on, check the shelving unit to the right. The code's on a piece of paper on the bottom shelf. What's behind this particular door doesn't get a punchline, just a floating dog creature in a puritan hat with rubber hose arms hovering over a suitcase, and Jack has nothing to say about it either. Neither did I, honestly. Grab the coins and keep moving.

The Four Codes Nobody Needed to Find

The remaining four don't tie into anything the game asks you to do. They're pure developer indulgence, the kind of thing that only surfaces if someone's willing to punch in numbers that have nothing to do with level design and everything to do with dates that mattered to whoever built this game.

1920 opens on an older, more primitive version of Jack Pepper's office, no reward attached, just a look at what the game apparently used to be during its early conceptual stage.

2019 turns up a computer screen and a blackboard reading "Insert Fumi team here," with a handwritten note underneath signed "Fumi Team xoxo." A cheeky self insert, and one that still pays out 10 coins despite not needing to.

0316 is the wrestling reference, a framed portrait of a bald, bearded, shirtless man standing behind a rock, which is about as direct a nod to Stone Cold Steve Austin as a game can get without a lawsuit. Another 10 coins here.

1224 is the one that actually unsettles a little. Smoke clears to reveal a blood stained surgical bed, scattered scissors, an open medical case, and a pair of Groucho Marx glasses resting on a block of cheese for reasons the game never bothers explaining. Jack calls it creepy, which is putting it mildly. Grab the coins and leave.

One detail worth flagging for anyone who is skitish and punching these in back to back. After enough codes in quick succession, a solid black mouse statue quietly appears in the room without any dialogue or explanation. It doesn't do anything, but it's the kind of thing a level designer plants specifically to make you look over your shoulder later, and it worked.