The Past Within Walkthrough: Co-op Puzzle Route, Achievements, and Secret Scrolls

The Past Within is built around a simple but easy-to-break rule: one player sees The Past, the other sees The Future, and most puzzles only make sense when both players describe exactly what is on their screen. This walkthrough is written for real co-op play first, with route notes for both Bee and Butterfly, achievement cleanup, secret-scroll notes, and a few places where the safest answer is not a memorized code but a clean callout between partners.

The guide uses the July 10, 2026 source set. Steam officially lists The Past Within as Rusty Lake’s co-op-only point-and-click adventure, released on November 2, 2022, with 24 Steam achievements. The full route below is assembled from official Steam metadata, readable walkthrough references, achievement guides, and verified video walkthrough metadata. Two Steam Community infographic-style pages were saved but did not expose readable puzzle diagrams in text, so they are not treated as factual support for exact solution graphics.

Before You Start#

Both players need their own copy of the game and a way to talk. Do not plan around old single-PC workarounds: one readable Steam guide for that method is now titled as no longer working, and Steam’s current store text describes The Past Within as co-op-only. If you are trying to complete everything, run the game twice so each person can play both perspectives.

Choice	What It Changes	Best Use
Bee	Different Chapter 1 picture order, times, codes, chess route, and Chapter 2 pointer positions.	Use this if both players selected Bee. Do not mix Bee notes with Butterfly.
Butterfly	Same story structure, but several puzzle values are different.	Use this if both players selected Butterfly. This is the most commonly documented 100% route.
Past	2D room, coffin, stove, clock, stained glass, altar, diary, piano, and golden cube.	Best for the player who likes object hunting and room navigation.
Future	3D cubical machine, screen prompts, switch panels, lab, radio, blackboard, and black cube.	Best for the player who is comfortable reading machine feedback and relaying patterns.

Co-op Callouts That Prevent Most Mistakes#

The Past Within punishes vague calls. Use exact language: “top-left picture,” “red pointer at 3,” “second row, fourth tooth,” “do not leave the tooth screen yet,” or “I changed the Future cube.” If a puzzle uses a visual grid that this text guide cannot reliably reproduce, let the player who sees the live pattern lead the callout and let the other player repeat it back before clicking.

• Say the route name first. Start every session by confirming “Bee” or “Butterfly.”
• One player reads, the other repeats. This prevents swapped left/right and top/bottom mistakes.
• Never leave an achievement puzzle early. “A tooth for a tooth,” “Checkmate,” “Frankenstein,” and “Hidden treasure” can fail if you back out or make false moves.
• Use the achievement cleanup table before Chapter 2 ends. Several achievements are easier to miss than the story puzzles.
• Do not skip the credits. The Chapter 2 ending achievements require watching through the credit sequence.

Chapter 1 Walkthrough#

Chapter 1 is about connecting the Past room to the Future machine, recovering bone, flesh, and blood from Albert, and sending the golden cube forward. The broad route is the same in Bee and Butterfly, but many values change.

1. Connect the Cubical Device

1. Past opens the letter and reads the year: 1926.
2. Future turns on the cubical device, enters 1926, and describes the flashing 3×3 pattern.
3. Past presses the matching buttons on the box, takes the matches, and later sends the matchbox to Future.
4. Future opens the matchbox, takes the switch, installs it under P-17, and turns it on.

Chapter 1 Setup	Bee	Butterfly
Future picture panel	House, Bee, Crow, Rose and Albert.	Crow, Butterfly, Tree, Rose and Albert.
Past floor box symbols	Sword, cross-hair, vertical line with bottom circle, rectangle with two small squares.	Vertical line with right circle, capital T, wavy line with left circle, vertical line with bottom circle.
Smoke/clock time	13:15.	17:15.
Drawer after portrait key	Bottom drawer.	Middle drawer.

Past uses coal and matches in the stove, heats the soup, then reports the stove-gauge pattern so Future can set the matching rows on the machine. The exact gauge is visual; if your run differs from the text references, trust the live screen. Future takes the battery, installs it, and gives the clock time to Past. Past sets the clock, picks up the portrait key, opens the correct drawer, takes the snow mask, and wears it at the mirror for Behind the mask.

2. Stained Glass, Lens, and Coffin

Future installs the fan key and photo slide, then uses the eyepiece. Past clicks stained-glass images as they are highlighted. Use the table below for the stable route values captured from readable references, but still communicate each symbol before clicking.

Checkpoint	Bee	Butterfly
First eyepiece pointers	Arrow 9, circle 6, cross 3.	Arrow 8, circle 5, cross 4.
First glass clicks	Mountain, tree, cube.	Butterfly, tree.
Second eyepiece pointers	Arrow 10, circle 7, cross 1.	Arrow 6, circle 2, cross 8.
Second glass clicks	Butterfly, knife.	Butterfly, mountain, mask, knife.
Third eyepiece pointers	Arrow 11, circle 8, cross 4.	Arrow 11, circle 7, cross 3.
Third glass clicks	Butterfly, mountain, cube, knife.	Butterfly, cube, knife.
Final eyepiece pointers	Arrow 3, circle 12, cross 9.	Arrow 1, circle 11, cross 6.

After Future looks through the lens, click Rose repeatedly for Who is that?. Future should also click the mouse whenever it appears; the Chapter 1 route has three mouse moments for Squeak.

Coffin and Tooth Route	Bee	Butterfly
Coffin letters	Use L from the top line and VAERO from the bottom line.	Use ART from the top line and NBM from the bottom line.
Future riddle code	IDAV.	RVDB.
Tooth achievement warning	Do not leave the tooth puzzle when Past gets the tooth. Future must finish the fifth matching box click to unlock A tooth for a tooth.

Past opens the altar, takes the mouth opener, and follows Future’s flashing-tooth callouts. Then Past lights the candles, takes the key from the melted candle, opens the diary, and shades the diary squares based on Future’s slides.

Diary Item	Square
Bee or Butterfly	Bottom-right.
Ida	Top-right.
Rose	Bottom-left.
Cubical Device	Bottom-right.
Chess piece	Top-left.
Dark Soul	Top-right.

3. Blood Codes, Soup, Chess, and the Golden Cube

Past cuts Albert’s ear, then uses the altar code chain with Future. These are the stable code chains captured from the readable references.

Sequence	Bee	Butterfly
First keypad code	2Y3Z1X.	3XZY21.
Second code after wall picture	Y3X1Z2.	X2Y13Z.
Third code from mirror	312ZYX.	YX31Z2.
Fourth code from floor box	XZY312.	XZY312.
Gem from soup	Orange gem.	Green gem.

Past pours the hot soup into the bowl, eats it with the spoon, inserts the gem at the altar, collects blood with the cotton swab and bottle, then places bone, flesh, and blood into the Past-side device for Bone, Flesh and Blood. The scroll gives the Future year: 1984. Future enters it for The year of The Future.

Late Chapter 1	Bee	Butterfly
Cassette/clock time	14:35.	19:45.
Past black chess route	E5, E1, C3, C6.	A5, D2, B2, F6.
Future white chess route	A6, A3, F3, D1, D6.	F3, A3, C1, C6, A6.
Final Past clock time	15:20.	21:10.
Final cube hold	Hold the down arrow for 10 seconds.	Hold the up arrow for 10 seconds.

For Checkmate, make the chess moves cleanly without false movement. After the coins go on Albert’s eyes, check the coffin again for The Devil. At the end, both players hold their cube direction long enough to complete Chapter 1 and unlock The Past has changed and The Future is ever changing.

Chapter 2 Walkthrough#

Chapter 2 turns the Chapter 1 ritual into a lab reconstruction. Future works around the large machine and lab room, while Past controls the cubical device and its hidden mechanical panels.

1. Opening Code, Radio, Piano, and Tooth Key

1. Future reads the starting notes.
2. Past enters Z1X23Y on the cubical device.
3. Future takes the black cube, matches, and glass, fills the glass with water, checks the mirror, and tunes the radio near 97 to trigger Harvey’s Song after checking the mirror again.
4. Future inserts the black cube into C-9 and reports the pointer positions.
5. Past sets the eyepiece markers, takes the music key, unlocks the piano, and presses random keys for Victor.

Chapter 2 Radio Step	Bee Frequency	Butterfly Frequency	Past Piano Notes
First phrase	91.4	78.3	AGAB.
Second phrase	72.0	114.3	CDEG.
Third phrase	85.3	103.7	EDEC.
Fourth phrase	110.2	89.1	BAGA.

Past takes the tooth key, unlocks the tooth panel, and reports the switch pattern. Future sets the matching cabinet switches, takes chalk and the scalpel, draws on the blackboard, and Past enters X3Z1Y2. Future circles the requested symbols on the blackboard, takes the hammer, breaks the large tooth, vacuums the fragments, and flips the Bone switch.

2. Pointer Positions and Ear Route

Each time Future activates a body substance, Future presses the round button and calls the pointer positions. Past then sets the eyepiece markers.

Pointer Checkpoint	Bee	Butterfly
Opening black cube	Red 3, white 6, black 9.	Red 1, white 3, black 11.
After Bone	Red 9, white 11, black 3.	Red 6, white 1, black 4.
After Flesh	Red 10, white 2, black 5.	Red 10, white 12, black 7.
After Blood	Red 8, white 4, black 6.	Red 3, white 5, black 9.
After snow mask	Red 11, white 3, black 7.	Red 5, white 11, black 2.

Past uses the nut driver, finds the three hidden gears around the wooden device, installs them, lowers the doll, takes the hook, and raises the ear for Ear on the inside. Keep clicking the Bee or Butterfly until it lands in one of the hidden gear compartments, then close it for Breaking in. Future should click the black mouse repeatedly for No way out.

Future opens the tall cabinet, checks the computer, and sends the switch-code information. Past sets the switches, then Future enters the arrow route.

Chapter 2 Arrow Code	Route
Bee	Left, up, up, down, left, up.
Butterfly	Right, left, left, up, right, down.

Past enters Y3X1Z2 to reveal the map, then guides Future through the maze targets. Future takes the ear, cuts the flesh with the scalpel, gathers dark powder, makes coffee, lights the burner, and sets up water, coffee, acid, and flesh for the lab sequence.

3. Flesh, Blood, Albert, Masks, and Ending

The flesh sequence is one of the main missable achievement checks. Past enters each lab code, Future reads the instructions, and Future adds the liquids without mistakes. The captured references agree on this code order:

Flesh Stage	Past Code	Future Action
Stage 1	3X2Z1Y	Add acid, water, and hot coffee in the instructed order.
Stage 2	1Y3X2Z	Use the next clue to match the flesh shape.
Stage 3	2Z1X3Y	Use the surface clue and do not guess.
Stage 4	1Y2X3Z	Use the final body-part clue. If no mistake was made, Frankenstein unlocks.

After the Flesh switch, Past receives the valve. Future lures the large Bee or Butterfly from the vent, takes the key from the dead mouse, opens the other cabinet, takes the second valve, and starts the blood console. The symbol lists below are callout order, not lore order. Press the red button after each symbol.

Blood Console Side	Symbols to Call
Future	Two rectangles, capital T, cross-hair, vertical line with left circle, rectangle with two small squares, sword, horizontal line with top circle, wavy line.
Past, Bee route	Deer, man, crow, house, tree, heart, bee, eye.
Past, Butterfly route	Deer, man, crow, house, tree, heart, butterfly, eye.

Future flips the Blood switch, Past uses the hex key to reveal the scope, and the pair solves the scope-to-black-cube image sequence. The exact scope patterns are visual; have Past describe each pattern and Future enter it on the black cube. When the machine breaks, Future clicks Albert, opens his cabinet scene, and reads the pocket code: 3XY21Z. Past enters it, Future circles eyes, future, mask, gems, and cube on the blackboard, then takes the golden key and the three masks.

Use the masks in order. Snow mask gives the voodoo needle; Past uses it on the doll’s eye for Dead eye and takes the white gem. Deer mask gives the switch pattern for the red gem. Music mask points to the radio; Past plays FGDC for the golden gem. Place the gems white, red, golden from left to right on the first try for Hidden treasure.

Past reads the golden cube pattern and Future enters it on the big machine. Future gives the black cube to Albert, then both players hold their cubes for 10 seconds. Watch the full ending and credits for Rooted in The Past and Branching out.

Achievement Cleanup#

Steam appdetails and the Steam global achievement API confirm 24 achievement records. Steam’s public achievement web page did not expose the localized list in the saved text, so the names and trigger notes below are cross-checked from readable achievement references.

Achievement	Side / Chapter	How to Get It	Risk
Behind the mask	Past 1	Wear the snow mask at the mirror.	Story route.
Bone, Flesh and Blood	Past 1	Place bone, flesh, and blood into the Past-side device.	Story route.
The Past has changed	Past 1	Finish Chapter 1 from the Past side.	Story route.
Catch me if you can	Past 1	Keep clicking the Bee or Butterfly as it moves, including the rose and lantern moments after the vase breaks.	Missable if ignored.
You know what to do	Past 1	Inspect the crow picture clue, then check the mirror.	Missable.
The Devil	Past 1	After Albert’s corrupted soul leaves the coffin, inspect the coffin again and take the tarot card.	Missable.
Who is that?	Future 1	Look through the lens after the stained-glass puzzle and click Rose until the scare triggers.	Missable.
The year of The Future	Future 1	Enter 1984 after Past reads the scroll.	Story route.
The Future is ever changing	Future 1	Finish Chapter 1 from the Future side.	Story route.
Checkmate	Future 1	Finish the chess puzzle without false moves.	Missable; use the route table.
A tooth for a tooth	Future 1	Complete the full Future-side tooth box sequence after Past obtains the tooth.	Missable if either player leaves too early.
Squeak	Future 1	Click the mouse at all three Chapter 1 appearances.	Missable.
Ear on the inside	Past 2	Raise the ear with the hook mechanism.	Story route.
Dead eye	Past 2	Use the voodoo needle on the doll’s eye.	Story route.
Rooted in The Past	Past 2	Finish Chapter 2 and do not skip the credits.	Do not skip credits.
Breaking in	Past 2	Trap the Bee or Butterfly in one of the hidden gear compartments.	Missable.
Victor	Past 2	Press random piano keys for a while after unlocking the piano.	Missable.
Hidden treasure	Past 2	Place the white, red, and golden gems correctly on the first attempt.	Missable if a gem is misplaced.
All ears	Future 2	Receive the ear in the lab room.	Story route.
There will be blood	Future 2	Complete the resurrection machine sequence after bone, flesh, and blood are processed.	Story route.
Branching out	Future 2	Finish Chapter 2 and do not skip the credits.	Do not skip credits.
Frankenstein	Future 2	Complete the flesh liquid process without a wrong pour.	Missable; read every instruction twice.
No way out	Future 2	Repeatedly click the black mouse while it runs around the Future room.	Missable.
Harvey’s Song	Future 2	Tune the radio around 97.0, then check the mirror.	Missable; the tuning is precise.

Secret Scrolls and Extra Minigame#

The hidden scrolls are community-discovered extras tied to Rusty Lake clues. Treat them as bonus material rather than required completion.

Extra	Confirmed Route	Notes
MemoryCube Recording 02481 scroll	In the Future memory-year prompt, enter 1867, then solve the smoke-and-gas discharge slider puzzle with top 2, middle 4, bottom 4.	Readable Secret Scrolls reference ties this to Albert’s birth year.
MemoryCube Recording 02715 scroll	The clue points to symbols in the books from an official trailer, then to the large floor box in The Past.	The saved readable text confirms the clue route, but the exact symbol diagram was image-only in the captured source, so this article does not restate an unverified symbol order.
Run Harvey Run minigame	Start as Future, enter 1935 at the memory-year prompt, complete the discharge/switch setup, take the green floppy disk, and insert it.	The readable route confirms the six-switch pattern as up, down, down / up, down, up after the discharge step.

Video Walkthrough References#

The two videos below were verified through YouTube oEmbed metadata. Both are by Thias Lhs and match the requested Chapter 1 and Chapter 2 Past/Future walkthrough topics.

Common Mistakes#

• Mixing Bee and Butterfly values. Most “wrong code” problems come from using the other route’s table.
• Clicking before repeating the callout. If a puzzle has rows, columns, or clock positions, repeat it back before committing.
• Backing out of the tooth puzzle too early. Stay until the Future player completes the fifth matching box click.
• Guessing the flesh liquids. One wrong pour ruins Frankenstein.
• Skipping the credits. The ending achievements need the full credit sequence.
• Treating old solo guides as current instructions. Use real co-op unless a current platform-specific workaround is independently verified.

Sources and Credits#

Official information and images are from the The Past Within Steam page and Rusty Lake. Walkthrough, achievement, and secret-scroll steps were cross-checked against readable community walkthrough references and verified video walkthrough metadata. Screenshots in this article are official Steam screenshots; no competitor guide images are used.