Cover of The Penumbral Index by Yara Hallowell

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The Penumbral Index

The Hallowmere Lectures · Book 2

One card is missing from the catalog. One name has been erased from the ledger. Marta Renn knows both facts — and knows she was the one who signed the form that made it happen.

One card is missing from the catalog. One name has been erased from the ledger. Marta Renn knows both facts — and knows she was the one who signed the form that made it happen. It is wartime in Hallowmere. The Public Record Library runs blackout drills, processes citizens through numbered cards, and houses a secret tool no one is supposed to name: the Penumbral Index — translucent sheets that reveal which lives are still flexible and which have already been decided. When an extended night drill puts Marta at the Index table, she sees the patterns for the first time from the inside: names sorted into baskets marked R, C, and X. Relocation. Correction. Erasure. Among them, she recognises people she knows. She has one night. A handful of allies she cannot fully trust. Three lives she might be able to tilt — if she is willing to pay for each one with a piece of herself she cannot get back. The Penumbral Index is a novel about bureaucracy as violence, precision as resistance, and the distance between signing a form and understanding what it means. A prequel to The Secretarium. The Hallowmere Lectures begin here.

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PublicationAvailable
FormatsPaperback
Publication dateFebruary 27, 2026
Kindle print length180 pages
ISBN978-9190145326
Kindle ASINB0GN9MZ69D
LanguageEnglish
ExtentFull-length novel
Paperback pages248 pages
Word count63 000 words
GenreLiterary speculative fiction
SeriesThe Hallowmere Lectures
Book in seriesBook 2
Story scopePrequel in The Hallowell Lectures series
ToneQuietly tense, procedural, morally sharp; low-spectacle, high-pressure
PublisherUTP House
Good to know

The “action” is administrative—blackouts, ledgers, Security protocols, and the Index sheets that reveal hidden routes between records.

Ideal for readers who like

Slow-burn institutional suspense, controlled prose, rule-systems, and protagonists who resist through precision rather than speeches.

Content note

Themes of state control, forced disappearance via bureaucracy, and sustained psychological stress; no gore-forward violence.

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In the quiet moments, when a drawer slid shut with its soft wooden thud and no one stood at the counter, she let her mind rest for a few breaths on the three lives she had tilted. Matthew Holt, held in review. Tomas Renn, on a rail line near a river. The stranger marked with the star, somewhere under another roof. Daniel, absent from every ledger, present in the way her hand moved, in the way Howe’s voice changed on certain words, in the slight hesitation before Corin told a clerk to stamp a harsher code. The Penumbral Index was gone from the building. Its crate would soon sit in some windowless archive room, its contents photographed, catalogued, perhaps broken up or destroyed once someone decided their methodology was no longer needed. The pattern it had revealed did not vanish with it.

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Every correction leaves a shadow.

It’s the year 1937. Air-raid drills drop the city of Hallowmere into darkness three times a week. Marta Vance, a junior librarian in the Public Record Library, is expected to lock her desk, dim her lamp, and wait it out.

Instead she hides a forbidden tool: the Penumbral Index, translucent sheets that only align in low light and reveal what the official ledgers erase. Every drill, another catalog card goes missing. Every alignment points toward a sealed sub-level and a new set of names marked for “precautionary custody.”

Marta’s husband already disappeared under the same euphemism. The Index finally shows her the truth: the blackout is cover for raids, and tonight’s list includes people she knows. With one extended drill as her window, she must use the Index, a borrowed lock code, and an inspector’s misplaced trust to break into the purge room—and decide who, if anyone, she can pull back from the dark.

Story

In the quiet moments, when a drawer slid shut with its soft wooden thud and no one stood at the counter, she let her mind rest for a few breaths on the three lives she had tilted. Matthew Holt, held in review. Tomas Renn, on a rail line near a river. The stranger marked with the star, somewhere under another roof. Daniel, absent from every ledger, present in the way her hand moved, in the way Howe’s voice changed on certain words, in the slight hesitation before Corin told a clerk to stamp a harsher code. The Penumbral Index was gone from the building. Its crate would soon sit in some windowless archive room, its contents photographed, catalogued, perhaps broken up or destroyed once someone decided their methodology was no longer needed. The pattern it had revealed did not vanish with it.

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