The safe in Room 13 is the first real puzzle Hollowbody throws at you, and it does not give you the answer outright. The code is buried in two photographs and a handful of environmental details that the game expects you to piece together yourself. Miss the clues and you will be standing at a keypad with no idea what to type.
This guide walks through every step, from reading the photographs to entering the correct code, so you can grab the Long Key and keep moving.
What is the Room 13 safe puzzle in Hollowbody?
Early in Hollowbody's first level, protagonist Mica explores a large abandoned building. After dealing with the first enemy encounter, you reach Room 13. On the wall sits a locked safe with a keypad. Opening it is not optional: the safe holds the Long Key, an item tagged Spare gate that the main story requires to continue.
The code is not written anywhere in plain sight. The game is a survival horror adventure game that leans into environmental storytelling, so the answer comes from reading the room rather than finding a note with digits on it.
The Room 13 safe keypad
Step 1: Find and examine both photographs
Before touching the keypad, search Room 13 for two photographs. Both are findable in the same space and both carry pieces of the puzzle.
- Birthday photograph: Shows a young woman celebrating a birthday alongside a child who appears to be around three or four years old.
- Graduation photograph: Shows three women in caps and gowns. One of them is visibly heavily pregnant.
The body on the floor belongs to Hellen Bridges, the former occupant of Room 13. The photographs document her personal history, and her birth year is established by other details in the room as October 2025.
Birthday photo clue in Room 13
Step 2: Work out Hellen's graduation year
Here is how the timeline breaks down from the clues:
Working backwards: if the child in the birthday photograph is roughly 3 to 4 years old, and Hellen was pregnant during graduation, the graduation took place approximately 3 to 4 years before that birthday photo was taken. Running the numbers against her birth year and the implied timeline puts the graduation at either 2051 or 2052. The correct answer is 2052.
Step 3: Enter the code and collect the Long Key
Walk up to the safe and interact with the keypad. Enter 2052. The safe opens immediately, and inside is the Long Key. Its item description confirms its origin: found in the Room 13 safe, tagged Spare gate. This key is required to progress through the level, so there is no way around this puzzle.
Long Key unlocks the next gate
Why does this puzzle work the way it does?
Hollowbody uses environmental storytelling to deliver puzzle solutions rather than handing them to you directly. Room 13 is the game's first test of that approach: the code is never written down, but every piece of information needed to calculate it exists in the room. The photographs establish a personal timeline for Hellen Bridges, and cross-referencing her birth year with the visual evidence in both photos produces the answer.
This design pattern appears throughout the game, so getting comfortable with reading rooms carefully will serve you well beyond this first puzzle. For more help navigating the game's challenges, check out the full Hollow Knight guides collection for similar puzzle-focused survival horror tips.
Quick reference: Room 13 safe solution
- Examine the birthday photograph (child aged 3-4)
- Examine the graduation photograph (Hellen is pregnant)
- Note Hellen Bridges' birth year: October 2025
- Calculate graduation year: 2052
- Enter 2052 on the keypad
- Collect the Long Key (tagged: Spare gate)
If you are just getting started with Hollowbody or want a broader look at puzzle-heavy adventure games, the guides section has you covered for whatever comes next.