Campaign setting · Call of Cthulhu 7e

Temporal Solutions

Modern civilians thrown a century into the past.
Ambrosia puts them to work against the Mythos.

At a glance

What kind of game is this?

Setting

1920s–1930s America

Pulp streets, telegrams, and secrets that still fit in a filing cabinet.

System

Call of Cthulhu 7e

Percentile investigation, Sanity loss, lethal fights — same rules spine.

Call of Cthulhu percentile dice and investigator sheet

Tone

Horror · 18+

Death, despair, racism, and sexism appear as period realities and themes.

Investigator facing a towering cosmic horror in fog

Beginner-friendly

Built so modern player knowledge is a feature of the fiction, not a table foul.

Before the jump

The end of the world

A worldwide doomsday scenario occurs and all hope is lost. Humanity gambles on an experimental device meant to send a small team about one year into the past to fix it.

What went wrong

Ten kilometers. One hundred years.

Instead of a surgical team hop, the device takes everything in a ~10 km radius back a full century. Your investigators were civilians caught in that accidental time warp.

Curse and blessing

They escaped the end of the world — and must live the rest of their lives in a past they are not used to.

Author’s inspiration

Yithian technology, reversed

Inspired by The Shadow Out of Time: the Great Race of Yith swaps minds across eras. Imagine a modern organization reverse-engineering that trick — experimental, unused — until desperation left no other option.

First contact

The Shadow Mistress

She claims to head the Project that saved you — and explains what has happened.
She speaks for an organization calling itself Ambrosia.

The organization

Ambrosia

Ambrosia recruits the temporally displaced to handle supernatural-related work. All PCs are assumed to work for Ambrosia — alongside a regular day job, if they wish.

Day job

Nurse, reporter, mechanic, academic — cover identities that pay rent.

Night work

Cases Ambrosia assigns: hauntings, cults, artifacts, missing persons.

Loyalty?

Salvation has a price. How much you trust the Shadow Mistress is your story.

Design thesis

Play on what players already know

Cthulhu tables often fight metagame knowledge of the 1920s. Temporal Solutions leans into it: your modern mind is in period clothes. The time jump also gives the campaign an isekai flavor — strangers forced to rebuild a life.

Table contract

Prejudice in the era

At first glance this setting may seem like women, people of color, and LGBTQ+ characters are restricted and discriminated against on every side. Racism and sexism are perennial problems — not easy to solve universally — but here removing those aspects would undermine the themes of the setting.

The Roaring Twenties and pulp Thirties are not meant to be pleasant. Players can, and perhaps should, fight to challenge that status quo — as great people did to create a better world.

Discuss lines and veils before play. Content warnings are not optional flavor.

Who you might be