The Last Jazz Train

Cinevva's analyzer read this game's design doc and its source, then wrote the brief below. "Make your own" hands it to the game creator as your opening message, so you start from a real spec rather than a one-line idea.

Create a narrative social-investigation game titled “The Last Jazz Train.” The player is a young journalist aboard a luxury overnight train in 1928 during a blizzard, investigating the disappearance of wealthy businessman Victor Bell. Bell has vanished before the train reaches New York, and the player must move through the train, question passengers and staff, collect evidence in a notebook, manage reputation with several groups, decode jazz clues, and reach one of three endings in the observation car. There is no combat or free walking: the core interaction is selecting locations, opening dialogue scenes, choosing responses, and satisfying evidence requirements.

Use a stylized 3D Art Deco train interior rendered in Three.js. Show a first-person/forward-facing view down a long narrow train carriage: dark wood floor and side walls, a deep burgundy velvet carpet, blue-black ceiling and structural arches, gold/brass trim, velvet seats on both sides, glowing blue night windows, warm ceiling/lamp light, cool blue rear light, and simple low-poly passenger figures spaced through the car. Snow particles should fall outside/in the scene, with subtle NPC bobbing and a very slight camera sway. Use fog and changing lighting to make each car feel distinct. The visual mood is glamorous, nocturnal, smoky, and ominous, with a palette of near-black navy, burgundy, brass/gold, cream, and icy blue. The interface overlays the 3D view with translucent near-black panels, thin gold borders, cream text, elegant serif display headings, and clean sans-serif body text. The attached visual shows the HUD: a top case header, large Notebook and Actions panels, and a three-button bottom navigation bar.

The train consists of exactly five sequential locations, navigated one car at a time with desktop Left/Right arrows or A/D, or mobile buttons Previous Car and Next Car. Disable Previous at the first car and Next at the last. Moving closes any open dialogue. The cars and narrative state are:
1. Sleeper Car, 8:10 PM, chapter “Nightfall — Departing Chicago.” Scene: velvet curtains sway with the rails; trunks, whispers, and sleepless money fill the aisle. Objective: get bearings and find who last saw Victor Bell. Lead: the porter knows who checked in under false names. Actions: Question the porter (Elias Reed, Train Staff), Read a discarded letter (Private Correspondence), Charm a socialite (Vivian Vale).
2. Dining Car, 9:05 PM, chapter “First Service — Silver and Suspicion.” Scene: champagne hides fear badly and people laugh too loudly when stock pages come out. Objective: win trust at the card table and pry open evening gossip. Lead: card players trade market rumors more freely than names. Actions: Join the card table, Compare notes with Detective Nora Quinn, Study the newspaper archive.
3. Lounge Car, 10:20 PM, chapter “Midnight Blue — Smoke, Gin, and Alibis.” Scene: brass, bourbon, and polished lies. Objective: test which passengers are protecting bootleggers. Lead: musicians hear things passengers think the band cannot understand. Actions: Talk to singer Ruby Saint, Shadow bootlegger courier Tommy Marrow, Eavesdrop behind the liquor cabinet.
4. Band Car, 11:40 PM, chapter “Late Set — Codes in Blue Notes.” Scene: trumpet echoes against lacquered wood while a storm rattles the windows. Objective: decode the band’s warning before the detective closes the wrong case. Lead: one lyric is not meant for the crowd. Actions: Question pianist Louis Mercer, Decode the changed lyric, Lean on bartender Mabel Cross.
5. Observation Car, 1:15 AM, chapter “Whiteout — Truth at the End of the Line.” Scene: snow smears the windows into ghostly silver; people come here to tell the truth or bury it. Objective: confront the hidden architect of the disappearance and choose the ending. Only action: Open the hidden hatch, confronting Victor Bell.

The top HUD must show “Case,” the game title, current chapter, current location, and time. The left Notebook panel must show the current objective, an Evidence list, and five reputation bars/numbers initially set to 50: Wealthy Socialites, Jazz Musicians, Train Staff, Bootleggers, and Detectives. Clamp reputation from 0 to 100 and update it from choices. If there is no evidence, show the exact idea that there is no hard evidence yet and the journalist should start asking the right people the wrong questions. The right Actions panel must show the current scene description, buttons for that location’s actions, and a Current lead. The bottom bar must have Previous Car, Listen to the Band, and Next Car. Pressing L or the Listen button triggers a jazz clue at any location: cycle through short observations that the trumpet/set list/lyrics are functioning like a telegram, point toward the last/rear car, and signal where scared people should run before dawn; add evidence “By listening closely, you realized the band is embedding directions in the music,” update the lead to cross-check the band’s warning with evidence, and open a dialogue-style overlay titled “The Night Set” with role “Jazz Mechanic.” The button text changes to “Revisit the Jazz Clue” after listening. Escape or Close dismisses dialogue.

Implement dialogue as a modal overlay with speaker role, speaker name, narrative text, selectable choice buttons, and Close. Each action opens its speaker scene. Choices can add a unique evidence clue, alter one or more reputations, update the current lead, and display the result text. Evidence IDs and essential branching content should include:
- Porter coat: Elias says Bell left his berth without luggage, while someone borrowed a porter coat and returned it damp with snow. Asking who could access uniforms adds “A porter coat was borrowed by someone impersonating staff” and +8 staff. Pressing about wealthy passengers gives -4 socialites and +4 staff.
- Ledgers: the perfume-stained letter links Bell to damaging financial ledgers and an impending crash; pocketing it adds that evidence and -3 bootleggers.
- Market warning: Vivian says elites were quietly warned to move money before Monday; offering discretion adds the clue and +7 socialites. Accusing her gives -8 socialites and -4 detectives.
- Cash out: conservative card play reveals Bell liquidated wealth into rail bonds and cash; add the clue and +3 socialites/+2 staff. Cheating to force a confession instead reveals bootleggers wanted the ledgers, adds “Bootleggers fear ledgers that connect them to respectable investors,” and gives -8 bootleggers/-5 socialites.
- Detective Quinn: sharing notes is locked until both porter_coat and cash_out are collected; when unlocked, add +10 detectives and establish this looks like a staged disappearance rather than a killing. Keeping clues hidden gives -6 detectives.
- Warning note: the newspaper’s marked “endless expansion” column has “They deserve warning, not rescue” written in pencil; take it as evidence.
- Song code: Ruby says Victor asked the band to play a coded song if the wrong men asked for him; asking what song adds evidence that song changes send warnings and +10 musicians. Offering to protect the band gives +5 musicians and points to the pianist.
- Rear car: Tommy reveals Bell’s books cover politicians, musicians, and millionaires; pretending you can recover the ledgers adds evidence that bootleggers planned to search the observation car and gives +6 bootleggers. Threatening him gives -10 bootleggers.
- Class warning: eavesdropping reveals Bell wanted to warn staff as well as investors; recording it adds the clue and +4 staff/-2 socialites.
- Hatch: Louis Mercer says Bell staged a false death because the truth was bigger than one murder. Asking where Bell hides is locked until song_code and rear_car are collected; then it adds “Bell is hiding near the observation platform hatch behind the rear car paneling” and +8 musicians. His alternate compassionate response gives +4 musicians/+3 staff.
- Lyric: the changed line “When the market falls, ride the last car west” ties the escape to the rear; writing it down adds the lyric clue and +6 musicians.
- Goodwill: Mabel says Bell paid for coffee and blankets in third class before vanishing; asking who benefited adds evidence that he helped workers and gives +8 staff.

At the observation car, Victor Bell is alive behind the panel, in shirtsleeves. His ledgers connect train wealth to bootlegging, market fraud, and an approaching crash. Present three final choices with disabled/locked states and explanatory locked text until requirements are met: (1) “Expose the truth to everyone on board,” requiring hatch and market_warning; result: call Quinn, staff, and passengers together, causing panic and honesty as elites turn on one another and workers hear what was hidden. Ending name: “The Truth Train,” with +8 detectives, +6 staff, -12 socialites. (2) “Help Bell escape at Albany and release the story later,” requiring hatch and song_code; coordinate with Ruby and Elias so Bell slips off before dawn and leaves the ledgers; ending “Blue Note Exit,” with +10 musicians, +6 staff, -4 detectives. (3) “Keep the ledgers and bargain for your own future,” requiring hatch and bootleg_ledgers; leave with the notebook instead of Bell and gain leverage over editors, gangsters, and investors; ending “Empire by Deadline,” with +4 bootleggers, -8 socialites, -10 detectives. Once an ending is reached, show a toast and replace the objective with a case-closed message naming the ending; allow replaying conversations to pursue another ending.

Use responsive desktop/mobile layout. On narrow screens, stack or scroll the Notebook and Actions panels while retaining the bottom controls and dialogue usability. Include subtle toast notifications for evidence added, lead updates, jazz clue caught, and ending reached. Ensure buttons are touch-friendly and support pointer input. The game should expose enough state to support testing: current location/index, time, evidence IDs/count, reputation values, current lead, current dialogue, ending, and whether the player listened to the band.