diff --git a/PlotLine.Tests/Program.cs b/PlotLine.Tests/Program.cs
index 6b49604..e55cf85 100644
--- a/PlotLine.Tests/Program.cs
+++ b/PlotLine.Tests/Program.cs
@@ -71,6 +71,7 @@ var tests = new (string Name, Action Test)[]
     ("Lean import removes replay links while retaining progress", LeanImportRemovesReplayLinksWhileRetainingProgress),
     ("Story Intelligence progress does not prematurely report safe close", StoryIntelligenceProgressDoesNotPrematurelyReportSafeClose),
     ("Structural import creates scenes before Word sync", StructuralImportCreatesScenesBeforeWordSync),
+    ("Structural import creates first scene without placeholder", StructuralImportCreatesFirstSceneWithoutPlaceholder),
     ("Structural import persists paragraph mapping and source text", StructuralImportPersistsParagraphMappingAndSourceText),
     ("Structural import persists canonical scene source text", StructuralImportPersistsCanonicalSceneSourceText),
     ("Structural import adds summaries without extra scene AI calls", StructuralImportAddsSummariesWithoutExtraSceneAiCalls),
@@ -1727,6 +1728,18 @@ static void StructuralImportCreatesScenesBeforeWordSync()
     Assert(onboarding.Contains("BuildSceneMarkerInstructions(structuralScenes, result.SceneMappings)", StringComparison.Ordinal), "Permanent SceneIDs should exist before Word marker instructions are built.");
 }
 
+static void StructuralImportCreatesFirstSceneWithoutPlaceholder()
+{
+    var root = Path.Combine(AppContext.BaseDirectory, "../../../../PlotLine");
+    var migration = File.ReadAllText(Path.Combine(root, "Sql/157_Phase25B_OnboardingBuildFirstSceneInsert.sql"));
+
+    Assert(migration.Contains("CREATE OR ALTER PROCEDURE dbo.Onboarding_ManuscriptBuild_Create", StringComparison.Ordinal), "Forward migration should update the onboarding build stored procedure.");
+    Assert(migration.Contains("IF @SceneID IS NOT NULL", StringComparison.Ordinal), "First scene handling should only update an existing placeholder when one exists.");
+    Assert(migration.Contains("ELSE\r\n            BEGIN\r\n                INSERT dbo.Scenes", StringComparison.Ordinal)
+        || migration.Contains("ELSE\n            BEGIN\n                INSERT dbo.Scenes", StringComparison.Ordinal), "First scene handling should insert a scene when no placeholder exists.");
+    Assert(migration.Contains("SET @SceneID = NULL;", StringComparison.Ordinal), "Scene cursor should clear SceneID between rows.");
+}
+
 static void StructuralImportPersistsParagraphMappingAndSourceText()
 {
     var root = Path.Combine(AppContext.BaseDirectory, "../../../../PlotLine");
diff --git a/PlotLine/Sql/157_Phase25B_OnboardingBuildFirstSceneInsert.sql b/PlotLine/Sql/157_Phase25B_OnboardingBuildFirstSceneInsert.sql
new file mode 100644
index 0000000..bd000a1
--- /dev/null
+++ b/PlotLine/Sql/157_Phase25B_OnboardingBuildFirstSceneInsert.sql
@@ -0,0 +1,235 @@
+SET ANSI_NULLS ON;
+GO
+SET QUOTED_IDENTIFIER ON;
+GO
+
+CREATE OR ALTER PROCEDURE dbo.Onboarding_ManuscriptBuild_Create
+    @UserID int,
+    @PreviewID uniqueidentifier,
+    @ProjectID int,
+    @BookID int,
+    @DocumentGuid uniqueidentifier,
+    @BindingVersion int = 1,
+    @ChaptersJson nvarchar(max),
+    @ScenesJson nvarchar(max),
+    @CharactersJson nvarchar(max)
+AS
+BEGIN
+    SET NOCOUNT ON;
+    SET XACT_ABORT ON;
+
+    IF @DocumentGuid IS NULL OR @DocumentGuid = '00000000-0000-0000-0000-000000000000'
+        SET @DocumentGuid = NEWID();
+
+    DECLARE @ExistingBuildID int;
+    SELECT @ExistingBuildID = OnboardingManuscriptBuildID
+    FROM dbo.OnboardingManuscriptBuilds
+    WHERE PreviewID = @PreviewID AND UserID = @UserID;
+
+    IF @ExistingBuildID IS NOT NULL
+    BEGIN
+        SELECT OnboardingManuscriptBuildID AS BuildID, PreviewID, ProjectID, BookID, ManuscriptDocumentID, Status, MarkerStatus,
+            ChaptersCreated, ScenesCreated, CharactersCreated, CharactersReused, SceneAppearancesCreated,
+            CAST(1 AS bit) AS AlreadyBuilt,
+            N'This manuscript has already been built into PlotDirector.' AS Message
+        FROM dbo.OnboardingManuscriptBuilds
+        WHERE OnboardingManuscriptBuildID = @ExistingBuildID;
+
+        SELECT TemporaryChapterKey, ChapterID FROM dbo.OnboardingManuscriptBuildChapterMap WHERE OnboardingManuscriptBuildID = @ExistingBuildID ORDER BY TemporaryChapterKey;
+        SELECT TemporarySceneKey, SceneID FROM dbo.OnboardingManuscriptBuildSceneMap WHERE OnboardingManuscriptBuildID = @ExistingBuildID ORDER BY TemporarySceneKey;
+        SELECT TemporaryCharacterKey, CharacterID, Created FROM dbo.OnboardingManuscriptBuildCharacterMap WHERE OnboardingManuscriptBuildID = @ExistingBuildID ORDER BY TemporaryCharacterKey;
+        RETURN;
+    END;
+
+    IF NOT EXISTS
+    (
+        SELECT 1
+        FROM dbo.Books b
+        INNER JOIN dbo.Projects p ON p.ProjectID = b.ProjectID
+        INNER JOIN dbo.ProjectUserAccess pua ON pua.ProjectID = p.ProjectID
+        WHERE b.BookID = @BookID
+            AND b.ProjectID = @ProjectID
+            AND b.IsArchived = 0
+            AND p.IsArchived = 0
+            AND pua.UserID = @UserID
+            AND pua.IsActive = 1
+    )
+        RETURN;
+
+    DECLARE @Chapters table (TemporaryChapterKey nvarchar(80) NOT NULL PRIMARY KEY, Title nvarchar(200) NOT NULL, SortOrder int NOT NULL, WordCount int NOT NULL);
+    DECLARE @Scenes table (TemporarySceneKey nvarchar(80) NOT NULL PRIMARY KEY, TemporaryChapterKey nvarchar(80) NOT NULL, Title nvarchar(200) NOT NULL, SortOrder int NOT NULL, WordCount int NOT NULL);
+    DECLARE @Characters table (TemporaryCharacterKey nvarchar(80) NOT NULL PRIMARY KEY, Name nvarchar(200) NOT NULL, ExistingCharacterID int NULL);
+
+    INSERT @Chapters (TemporaryChapterKey, Title, SortOrder, WordCount)
+    SELECT LEFT(JSON_VALUE(value, '$.TemporaryChapterKey'), 80),
+        LEFT(LTRIM(RTRIM(JSON_VALUE(value, '$.Title'))), 200),
+        TRY_CONVERT(int, JSON_VALUE(value, '$.SortOrder')),
+        COALESCE(TRY_CONVERT(int, JSON_VALUE(value, '$.WordCount')), 0)
+    FROM OPENJSON(@ChaptersJson)
+    WHERE NULLIF(JSON_VALUE(value, '$.TemporaryChapterKey'), N'') IS NOT NULL
+        AND NULLIF(LTRIM(RTRIM(JSON_VALUE(value, '$.Title'))), N'') IS NOT NULL;
+
+    INSERT @Scenes (TemporarySceneKey, TemporaryChapterKey, Title, SortOrder, WordCount)
+    SELECT LEFT(JSON_VALUE(value, '$.TemporarySceneKey'), 80),
+        LEFT(JSON_VALUE(value, '$.TemporaryChapterKey'), 80),
+        LEFT(LTRIM(RTRIM(JSON_VALUE(value, '$.Title'))), 200),
+        TRY_CONVERT(int, JSON_VALUE(value, '$.SortOrder')),
+        COALESCE(TRY_CONVERT(int, JSON_VALUE(value, '$.WordCount')), 0)
+    FROM OPENJSON(@ScenesJson)
+    WHERE NULLIF(JSON_VALUE(value, '$.TemporarySceneKey'), N'') IS NOT NULL
+        AND NULLIF(JSON_VALUE(value, '$.TemporaryChapterKey'), N'') IS NOT NULL
+        AND NULLIF(LTRIM(RTRIM(JSON_VALUE(value, '$.Title'))), N'') IS NOT NULL;
+
+    INSERT @Characters (TemporaryCharacterKey, Name, ExistingCharacterID)
+    SELECT LEFT(JSON_VALUE(value, '$.TemporaryCharacterKey'), 80),
+        LEFT(LTRIM(RTRIM(JSON_VALUE(value, '$.Name'))), 200),
+        TRY_CONVERT(int, JSON_VALUE(value, '$.ExistingCharacterID'))
+    FROM OPENJSON(@CharactersJson)
+    WHERE NULLIF(JSON_VALUE(value, '$.TemporaryCharacterKey'), N'') IS NOT NULL
+        AND NULLIF(LTRIM(RTRIM(JSON_VALUE(value, '$.Name'))), N'') IS NOT NULL;
+
+    IF NOT EXISTS (SELECT 1 FROM @Chapters) OR EXISTS (SELECT 1 FROM @Scenes s WHERE NOT EXISTS (SELECT 1 FROM @Chapters c WHERE c.TemporaryChapterKey = s.TemporaryChapterKey))
+        RETURN;
+
+    IF EXISTS (SELECT 1 FROM @Chapters WHERE SortOrder IS NULL OR SortOrder <= 0 OR WordCount < 0)
+        RETURN;
+    IF EXISTS (SELECT 1 FROM @Scenes WHERE SortOrder IS NULL OR SortOrder <= 0 OR WordCount < 0)
+        RETURN;
+
+    DECLARE @PlannedRevisionStatusID int = (SELECT TOP (1) RevisionStatusID FROM dbo.RevisionStatuses WHERE StatusName = N'Planned' ORDER BY SortOrder);
+    DECLARE @DefaultTimeModeID int = (SELECT TOP (1) TimeModeID FROM dbo.TimeModes ORDER BY CASE WHEN TimeModeName = N'Unknown' THEN 0 ELSE 1 END, SortOrder, TimeModeID);
+    DECLARE @DefaultTimeConfidenceID int = (SELECT TOP (1) TimeConfidenceID FROM dbo.TimeConfidences ORDER BY CASE WHEN TimeConfidenceName = N'Unknown' THEN 0 ELSE 1 END, SortOrder, TimeConfidenceID);
+
+    DECLARE @ChapterMap table (TemporaryChapterKey nvarchar(80) NOT NULL PRIMARY KEY, ChapterID int NOT NULL);
+    DECLARE @SceneMap table (TemporarySceneKey nvarchar(80) NOT NULL PRIMARY KEY, SceneID int NOT NULL);
+    DECLARE @CharacterMap table (TemporaryCharacterKey nvarchar(80) NOT NULL PRIMARY KEY, CharacterID int NOT NULL, Created bit NOT NULL);
+    DECLARE @BuildID int;
+    DECLARE @ManuscriptDocumentID int;
+    DECLARE @LinkedUtc datetime2 = SYSUTCDATETIME();
+
+    BEGIN TRANSACTION;
+
+    IF EXISTS (SELECT 1 FROM dbo.ManuscriptDocuments WHERE DocumentGuid = @DocumentGuid AND IsActive = 1 AND BookID <> @BookID)
+        THROW 51000, 'This manuscript document is already linked to another book.', 1;
+
+    SELECT @ManuscriptDocumentID = ManuscriptDocumentID FROM dbo.ManuscriptDocuments WHERE BookID = @BookID AND IsActive = 1;
+    IF @ManuscriptDocumentID IS NULL
+    BEGIN
+        INSERT dbo.ManuscriptDocuments (BookID, ProjectID, DocumentGuid, BindingVersion, CreatedByUserID, LastOpenedUtc, LastSyncUtc)
+        VALUES (@BookID, @ProjectID, @DocumentGuid, @BindingVersion, @UserID, @LinkedUtc, @LinkedUtc);
+        SET @ManuscriptDocumentID = CAST(SCOPE_IDENTITY() AS int);
+    END
+    ELSE
+    BEGIN
+        UPDATE dbo.ManuscriptDocuments
+        SET DocumentGuid = @DocumentGuid, ProjectID = @ProjectID, BindingVersion = @BindingVersion, LastOpenedUtc = @LinkedUtc, LastSyncUtc = @LinkedUtc
+        WHERE ManuscriptDocumentID = @ManuscriptDocumentID;
+    END;
+
+    INSERT dbo.OnboardingManuscriptBuilds (PreviewID, UserID, ProjectID, BookID, ManuscriptDocumentID)
+    VALUES (@PreviewID, @UserID, @ProjectID, @BookID, @ManuscriptDocumentID);
+    SET @BuildID = CAST(SCOPE_IDENTITY() AS int);
+
+    DECLARE @TempChapterKey nvarchar(80), @Title nvarchar(200), @SortOrder int, @WordCount int, @ChapterID int, @ChapterNumber decimal(9,2);
+    DECLARE chapter_cursor CURSOR LOCAL FAST_FORWARD FOR SELECT TemporaryChapterKey, Title, SortOrder, WordCount FROM @Chapters ORDER BY SortOrder, TemporaryChapterKey;
+    OPEN chapter_cursor;
+    FETCH NEXT FROM chapter_cursor INTO @TempChapterKey, @Title, @SortOrder, @WordCount;
+    WHILE @@FETCH_STATUS = 0
+    BEGIN
+        SET @ChapterNumber = (SELECT COUNT(*) + 1 FROM @ChapterMap);
+        INSERT dbo.Chapters (BookID, ChapterNumber, ChapterTitle, Summary, SortOrder, RevisionStatusID, IsLinkedToManuscript, ManuscriptDocumentID, ExternalReference, LinkedUtc)
+        VALUES (@BookID, @ChapterNumber, @Title, NULL, @SortOrder, @PlannedRevisionStatusID, 1, @ManuscriptDocumentID, @TempChapterKey, @LinkedUtc);
+        SET @ChapterID = CAST(SCOPE_IDENTITY() AS int);
+        INSERT @ChapterMap VALUES (@TempChapterKey, @ChapterID);
+        INSERT dbo.OnboardingManuscriptBuildChapterMap VALUES (@BuildID, @TempChapterKey, @ChapterID);
+        FETCH NEXT FROM chapter_cursor INTO @TempChapterKey, @Title, @SortOrder, @WordCount;
+    END;
+    CLOSE chapter_cursor; DEALLOCATE chapter_cursor;
+
+    DECLARE @TempSceneKey nvarchar(80), @TempSceneChapterKey nvarchar(80), @SceneID int, @SceneNumber decimal(9,2);
+    DECLARE scene_cursor CURSOR LOCAL FAST_FORWARD FOR
+        SELECT TemporarySceneKey, TemporaryChapterKey, Title, SortOrder, WordCount FROM @Scenes ORDER BY TemporaryChapterKey, SortOrder, TemporarySceneKey;
+    OPEN scene_cursor;
+    FETCH NEXT FROM scene_cursor INTO @TempSceneKey, @TempSceneChapterKey, @Title, @SortOrder, @WordCount;
+    WHILE @@FETCH_STATUS = 0
+    BEGIN
+        SELECT @ChapterID = ChapterID FROM @ChapterMap WHERE TemporaryChapterKey = @TempSceneChapterKey;
+        SET @SceneNumber = (SELECT COUNT(*) + 1 FROM @SceneMap sm INNER JOIN @Scenes s ON s.TemporarySceneKey = sm.TemporarySceneKey WHERE s.TemporaryChapterKey = @TempSceneChapterKey);
+        IF @SceneNumber = 1
+        BEGIN
+            SELECT TOP (1) @SceneID = SceneID FROM dbo.Scenes WHERE ChapterID = @ChapterID AND IsArchived = 0 ORDER BY SortOrder, SceneID;
+            IF @SceneID IS NOT NULL
+            BEGIN
+                UPDATE dbo.Scenes
+                SET SceneNumber = @SceneNumber, SceneTitle = @Title, SortOrder = @SortOrder, IsLinkedToManuscript = 1,
+                    ManuscriptDocumentID = @ManuscriptDocumentID, ExternalReference = @TempSceneKey, LinkedUtc = @LinkedUtc, UpdatedDate = SYSUTCDATETIME()
+                WHERE SceneID = @SceneID;
+            END
+            ELSE
+            BEGIN
+                INSERT dbo.Scenes (ChapterID, SceneNumber, SceneTitle, Summary, SortOrder, TimeModeID, TimeConfidenceID, RevisionStatusID, IsLinkedToManuscript, ManuscriptDocumentID, ExternalReference, LinkedUtc)
+                VALUES (@ChapterID, @SceneNumber, @Title, NULL, @SortOrder, @DefaultTimeModeID, @DefaultTimeConfidenceID, @PlannedRevisionStatusID, 1, @ManuscriptDocumentID, @TempSceneKey, @LinkedUtc);
+                SET @SceneID = CAST(SCOPE_IDENTITY() AS int);
+            END;
+        END
+        ELSE
+        BEGIN
+            INSERT dbo.Scenes (ChapterID, SceneNumber, SceneTitle, Summary, SortOrder, TimeModeID, TimeConfidenceID, RevisionStatusID, IsLinkedToManuscript, ManuscriptDocumentID, ExternalReference, LinkedUtc)
+            VALUES (@ChapterID, @SceneNumber, @Title, NULL, @SortOrder, @DefaultTimeModeID, @DefaultTimeConfidenceID, @PlannedRevisionStatusID, 1, @ManuscriptDocumentID, @TempSceneKey, @LinkedUtc);
+            SET @SceneID = CAST(SCOPE_IDENTITY() AS int);
+        END;
+        IF EXISTS (SELECT 1 FROM dbo.SceneWorkflow WHERE SceneID = @SceneID)
+            UPDATE dbo.SceneWorkflow SET ActualWordCount = @WordCount, UpdatedDate = SYSUTCDATETIME() WHERE SceneID = @SceneID;
+        ELSE
+            INSERT dbo.SceneWorkflow (SceneID, ActualWordCount) VALUES (@SceneID, @WordCount);
+        INSERT @SceneMap VALUES (@TempSceneKey, @SceneID);
+        INSERT dbo.OnboardingManuscriptBuildSceneMap VALUES (@BuildID, @TempSceneKey, @SceneID);
+        SET @SceneID = NULL;
+        FETCH NEXT FROM scene_cursor INTO @TempSceneKey, @TempSceneChapterKey, @Title, @SortOrder, @WordCount;
+    END;
+    CLOSE scene_cursor; DEALLOCATE scene_cursor;
+
+    DECLARE @TempCharacterKey nvarchar(80), @ExistingCharacterID int, @CharacterID int, @Created bit;
+    DECLARE character_cursor CURSOR LOCAL FAST_FORWARD FOR SELECT TemporaryCharacterKey, Name, ExistingCharacterID FROM @Characters ORDER BY Name, TemporaryCharacterKey;
+    OPEN character_cursor;
+    FETCH NEXT FROM character_cursor INTO @TempCharacterKey, @Title, @ExistingCharacterID;
+    WHILE @@FETCH_STATUS = 0
+    BEGIN
+        SET @Created = 0;
+        SELECT @CharacterID = CharacterID FROM dbo.Characters WHERE CharacterID = @ExistingCharacterID AND ProjectID = @ProjectID AND IsArchived = 0;
+        IF @CharacterID IS NULL
+            SELECT TOP (1) @CharacterID = CharacterID FROM dbo.Characters WHERE ProjectID = @ProjectID AND IsArchived = 0 AND UPPER(LTRIM(RTRIM(CharacterName))) = UPPER(@Title);
+        IF @CharacterID IS NULL
+        BEGIN
+            INSERT dbo.Characters (ProjectID, CharacterName, ShortName, CharacterImportance, ShowInQuickAddBar, DefaultDescription)
+            VALUES (@ProjectID, @Title, NULL, 8, 1, NULL);
+            SET @CharacterID = CAST(SCOPE_IDENTITY() AS int);
+            SET @Created = 1;
+        END;
+        INSERT @CharacterMap VALUES (@TempCharacterKey, @CharacterID, @Created);
+        INSERT dbo.OnboardingManuscriptBuildCharacterMap VALUES (@BuildID, @TempCharacterKey, @CharacterID, @Created);
+        SET @CharacterID = NULL;
+        FETCH NEXT FROM character_cursor INTO @TempCharacterKey, @Title, @ExistingCharacterID;
+    END;
+    CLOSE character_cursor; DEALLOCATE character_cursor;
+
+    UPDATE dbo.OnboardingManuscriptBuilds
+    SET ChaptersCreated = (SELECT COUNT(*) FROM @ChapterMap),
+        ScenesCreated = (SELECT COUNT(*) FROM @SceneMap),
+        CharactersCreated = (SELECT COUNT(*) FROM @CharacterMap WHERE Created = 1),
+        CharactersReused = (SELECT COUNT(*) FROM @CharacterMap WHERE Created = 0),
+        UpdatedUtc = SYSUTCDATETIME()
+    WHERE OnboardingManuscriptBuildID = @BuildID;
+
+    COMMIT TRANSACTION;
+
+    SELECT OnboardingManuscriptBuildID AS BuildID, PreviewID, ProjectID, BookID, ManuscriptDocumentID, Status, MarkerStatus,
+        ChaptersCreated, ScenesCreated, CharactersCreated, CharactersReused, SceneAppearancesCreated,
+        CAST(0 AS bit) AS AlreadyBuilt,
+        N'Your project structure has been created.' AS Message
+    FROM dbo.OnboardingManuscriptBuilds WHERE OnboardingManuscriptBuildID = @BuildID;
+    SELECT TemporaryChapterKey, ChapterID FROM dbo.OnboardingManuscriptBuildChapterMap WHERE OnboardingManuscriptBuildID = @BuildID ORDER BY TemporaryChapterKey;
+    SELECT TemporarySceneKey, SceneID FROM dbo.OnboardingManuscriptBuildSceneMap WHERE OnboardingManuscriptBuildID = @BuildID ORDER BY TemporarySceneKey;
+    SELECT TemporaryCharacterKey, CharacterID, Created FROM dbo.OnboardingManuscriptBuildCharacterMap WHERE OnboardingManuscriptBuildID = @BuildID ORDER BY TemporaryCharacterKey;
+END;
+GO