For novelists in revision
Plot Hole Finder for Your Whole Manuscript
Find the plot holes in your manuscript: each contradiction with both lines quoted, the chapters they're in, and the smallest fix.
Free to start. No card needed.
How to find plot holes in your manuscript
A plot hole is a place where your story breaks its own logic: a fact, date, secret or rule that one passage sets up and another contradicts. K.M. Weiland, author of Outlining Your Novel, calls them incomplete or incorrect causes and effects1. Many slip in during revision: you cut a scene or change an age, and a line 200 pages later keeps the old version. You know the story too well to see them, because memory fills each gap.
Copyeditors check against a written record: the Editorial Freelancers Association says copyediting involves preparing the style sheets that guide consistency and accuracy across the manuscript2. Keep yours in a story bible: each character's fixed facts, who learns what and when, where key objects are, and your world's rules. Add each chapter's date in story time, so ages and seasons add up. Then trace one thread at a time, such as a single secret: search the manuscript for its key word and test each mention against your notes.
Look hardest at subplots and the final chapters. Joseph Bates, in The Nighttime Novelist, asks whether every subplot has been concluded, and warns that late-novel monologues often mean information should have come earlier3. Before fixing anything, ask whether it's a slip or a choice, since a character's lie or a withheld clue may be the point. For a real slip, make the smallest fix: plant one line earlier, change the later one, or cut what you can't reconcile.
How it works
What does a plot hole finder do?
A plot hole finder reads your manuscript and flags the places where your story contradicts itself. Drop in a Word file or PDF, or paste chapters, and River reads all of it, in order, before it writes anything. It keeps notes much like a copyeditor's style sheet, then checks each later mention against them. Give it only some chapters and it checks those against each other, saying plainly that the rest wasn't checked.
It checks five kinds of problem. Facts: the key she threw away is back in her hand. Timeline: March becomes June in two days. Who knows what: a character quotes a note he never saw. World rules: magic without its price. Dropped threads: a setup that never pays off. It leaves pacing, style and taste alone, so the report stays short enough to act on. For notes on stakes and what to cut, use the AI book editor.
Every finding quotes both lines word for word, with their chapters; if River can't find both lines again, it drops the finding. Anything that looks deliberate is labeled Possibly intentional rather than reported as a mistake. No checker catches everything, though: a 2025 University of Washington study found that leading AI models struggled to spot plot holes, more so as stories got longer4. Keep beta readers for what a checker can't judge, like a motive that shifts or a choice that doesn't feel earned.
How it works
From manuscript to findings
Drop your manuscript
Drop in your manuscript or paste chapters. Over about 85,000 words? Upload a PDF so River reads every page.
River reads everything
It reads from the first page to the last, keeping track of facts, dates, secrets and rules.
Get your report
Each contradiction lands in your doc with both lines quoted, a how-sure label and the smallest fix.
Fix and follow up
Make the fixes you agree with, then keep going: River can draft fix lines or recheck a chapter.
Chapter 9Only Ruth and the coroner had seen the note.
Chapter 14Eli quoted the note word for word.
Who knows what · Sure. Smallest fix: show Ruth telling Eli in chapter 12, or let him guess wrong.
What you'll get
The contradictions in your book, with both lines side by side
- Each contradiction it finds, with both lines quoted
- The chapter each line is in, and how sure it is
- The smallest fix, so you change a line, not a chapter
Before and after
Your manuscript in. Every contradiction, with proof.
The Lighthouse Keeper, draft 3, as a Word file: 31 chapters, about 78,000 words.
1. The key Mara threw away · Facts · Sure Chapter 4: "She dropped the brass key through the grate and heard it hit the water." Chapter 19: "Mara turned the brass key in the lighthouse door." Nothing between chapters 4 and 19 gives it back to her. Smallest fix: one line in chapter 11 where Tomas hands her the spare. 2. March becomes June in two days · Timeline · Sure Chapter 2: "It was the first week of March, and the ferry still ran on its winter schedule." Chapter 6, two days later: "The June heat pressed against the glass." Smallest fix: change "June" in chapter 6, or show the months passing.
Both lines side by side, so you can tell a slip from a choice.
What lands in your doc
What's in your plot hole report
- A summary: how much of the book was read, findings by type, and which to fix first
- Each finding with Line A and Line B quoted word for word, with their chapters
- A how-sure label on every finding: Sure, Check this, or Possibly intentional
- The smallest fix for each, naming the one line or chapter you'd need to change
- Threads you opened: setups with no later payoff, quoted with the chapter they start in
- A timeline as written, chapter by chapter, whenever the dates or days disagree
Questions authors ask
Common questions
What is a plot hole?
A plot hole is a gap or contradiction in a story's logic, such as an only child who has a sister 20 chapters later. University of Washington researchers define plot holes as inconsistencies in a storyline that break the internal logic or rules of a story's world4. Common kinds include continuity errors, out-of-character behavior, impossible events and storylines that never resolve.
How do I check my manuscript for plot holes with River?
Drop your manuscript into the box at the top of this page, or paste a few chapters, then select Find my plot holes. River reads it all and writes the report into your free River workspace. There, it can draft a fix line in your voice for each finding marked Sure, in a separate doc. It can also check a revised chapter against the rest of the book.
Can the plot hole finder read my whole manuscript?
Yes. River reads the whole file, in order, before writing. The report opens with how much River read and the last line it reached, so you can see it got to the end. A Word file over about 85,000 words can be cut short, so upload a book that long as a PDF. If your book is in parts, drop in up to 10 files at once.
Will it flag my mystery or unreliable narrator as mistakes?
It tries not to. A clue you hold back on purpose, a lie a character tells, or a narrator who misleads the reader is labeled Possibly intentional, not counted as a slip. Because both lines are always quoted, you can see at a glance whether a finding is a real mistake or a choice you made.
Does it work for fantasy and science fiction rules?
Yes. World rules and their costs are one of the five things it checks. If chapter 3 says every spell costs a year of life, it tests later spells against that rule and quotes both lines of any clash. Fantasy novelist Brandon Sanderson's first law shows why it matters: an author's ability to solve conflict with magic depends on how well the reader understands it5.
Is my manuscript private?
Yes. Your manuscript and the report stay in your own River workspace unless you share them. River's privacy policy says it does not use your documents or drafts to train AI models. The outside AI services it uses work under data protection agreements that bar training on your content too. River reads your file but never edits it.
Is the plot hole finder free?
Yes, it is free to start, and you don't need a card. Your plot hole report opens in a River workspace, where you can edit it, share it or ask River to change it. Paid plans add more AI use and access to the most advanced models.
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