diff --git a/Source/FileLiberator/DownloadDecryptBook.cs b/Source/FileLiberator/DownloadDecryptBook.cs
index 257a17cf..e6112650 100644
--- a/Source/FileLiberator/DownloadDecryptBook.cs
+++ b/Source/FileLiberator/DownloadDecryptBook.cs
@@ -192,7 +192,7 @@ namespace FileLiberator
 			return dlOptions;
 		}
 
-		private List<AudibleApi.Common.Chapter> getChapters(IEnumerable<AudibleApi.Common.Chapter> chapters)
+		public static List<AudibleApi.Common.Chapter> getChapters(IEnumerable<AudibleApi.Common.Chapter> chapters)
 		{
 			List<AudibleApi.Common.Chapter> chaps = new();
 
@@ -200,17 +200,16 @@ namespace FileLiberator
 			{
 				if (c.Chapters is not null)
 				{
-					var firstSub = new AudibleApi.Common.Chapter
+					c.Chapters[0] = new AudibleApi.Common.Chapter
 					{
-						Title = $"{c.Title}: {c.Chapters[0].Title}",
+						Title = c.Chapters[0].Title,
 						StartOffsetMs = c.StartOffsetMs,
 						StartOffsetSec = c.StartOffsetSec,
-						LengthMs = c.LengthMs + c.Chapters[0].LengthMs
+						LengthMs = c.LengthMs + c.Chapters[0].LengthMs,
+						Chapters = c.Chapters[0].Chapters
 					};
 
-					chaps.Add(firstSub);
-
-					var children = getChapters(c.Chapters[1..]);
+					var children = getChapters(c.Chapters);
 
 					foreach (var child in children)
 						child.Title = string.IsNullOrEmpty(c.Title) ? child.Title : $"{c.Title}: {child.Title}";
diff --git a/Source/_Tests/FileLiberator.Tests/DownloadDecryptBookTests.cs b/Source/_Tests/FileLiberator.Tests/DownloadDecryptBookTests.cs
new file mode 100644
index 00000000..2c0726ed
--- /dev/null
+++ b/Source/_Tests/FileLiberator.Tests/DownloadDecryptBookTests.cs
@@ -0,0 +1,202 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using AudibleApi.Common;
+using Dinah.Core;
+using FileManager;
+using FluentAssertions;
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+
+
+namespace FileLiberator.Tests
+{
+	[TestClass]
+	public class DownloadDecryptBookTests
+	{
+		[TestMethod]
+		public void HierarchicalChapters_Flatten()
+		{
+			var expected = new Chapter[]
+			{
+				new()
+				{
+					Title = "Book 1: Part 1: Chapter 1",
+					StartOffsetMs = 0,
+					StartOffsetSec = 0,
+					LengthMs = 100000,
+				},
+				new()
+				{
+					Title = "Book 1: Part 1: Chapter 2",
+					StartOffsetMs = 100000,
+					StartOffsetSec = 100,
+					LengthMs = 100000,
+				},
+				new()
+				{
+					Title = "Book 1: Part 2: Chapter 3",
+					StartOffsetMs = 200000,
+					StartOffsetSec = 200,
+					LengthMs = 100000,
+				},
+				new()
+				{
+					Title = "Book 1: Part 2: Chapter 4",
+					StartOffsetMs = 300000,
+					StartOffsetSec = 300,
+					LengthMs = 100000,
+				},
+				new()
+				{
+					Title = "Book 2: Part 3: Chapter 5",
+					StartOffsetMs = 400000,
+					StartOffsetSec = 400,
+					LengthMs = 100000,
+				},
+				new()
+				{
+					Title = "Book 2: Part 3: Chapter 6",
+					StartOffsetMs = 500000,
+					StartOffsetSec = 500,
+					LengthMs = 100000,
+				},
+				new()
+				{
+					Title = "Book 2: Part 4: Chapter 7",
+					StartOffsetMs = 600000,
+					StartOffsetSec = 600,
+					LengthMs = 100000,
+				},
+				new()
+				{
+					Title = "Book 2: Part 4: Chapter 8",
+					StartOffsetMs = 700000,
+					StartOffsetSec = 700,
+					LengthMs = 100000,
+				}
+			};
+
+			var hierarchicalChapters = new Chapter[]
+				{
+					new()
+					{
+						Title = "Book 1",
+						StartOffsetMs = 0,
+						StartOffsetSec = 0,
+						LengthMs = 2000,
+						Chapters = new Chapter[]
+						{
+							new()
+							{   Title = "Part 1",
+								StartOffsetMs = 2000,
+								StartOffsetSec = 2,
+								LengthMs = 2000,
+								Chapters = new Chapter[]
+								{
+									new()
+									{   Title = "Chapter 1",
+										StartOffsetMs = 4000,
+										StartOffsetSec = 4,
+										LengthMs = 96000,
+									},
+									new()
+									{   Title = "Chapter 2",
+										StartOffsetMs = 100000,
+										StartOffsetSec = 100,
+										LengthMs = 100000,
+									},
+								}
+							},
+							new()
+							{   Title = "Part 2",
+								StartOffsetMs = 200000,
+								StartOffsetSec = 200,
+								LengthMs = 2000,
+								Chapters = new Chapter[]
+								{
+									new()
+									{   Title = "Chapter 3",
+										StartOffsetMs = 202000,
+										StartOffsetSec = 202,
+										LengthMs = 98000,
+									},
+									new()
+									{   Title = "Chapter 4",
+										StartOffsetMs = 300000,
+										StartOffsetSec = 300,
+										LengthMs = 100000,
+									},
+								}
+							}
+						}
+					},
+					new()
+					{
+						Title = "Book 2",
+						StartOffsetMs = 400000,
+						StartOffsetSec = 400,
+						LengthMs = 2000,
+						Chapters = new Chapter[]
+						{
+							new()
+							{   Title = "Part 3",
+								StartOffsetMs = 402000,
+								StartOffsetSec = 402,
+								LengthMs = 2000,
+								Chapters = new Chapter[]
+								{
+									new()
+									{   Title = "Chapter 5",
+										StartOffsetMs = 404000,
+										StartOffsetSec = 404,
+										LengthMs = 96000,
+									},
+									new()
+									{   Title = "Chapter 6",
+										StartOffsetMs = 500000,
+										StartOffsetSec = 500,
+										LengthMs = 100000,
+									},
+								}
+							},
+							new()
+							{   Title = "Part 4",
+								StartOffsetMs = 600000,
+								StartOffsetSec = 600,
+								LengthMs = 2000,
+								Chapters = new Chapter[]
+								{
+									new()
+									{   Title = "Chapter 7",
+										StartOffsetMs = 602000,
+										StartOffsetSec = 602,
+										LengthMs = 98000,
+									},
+									new()
+									{   Title = "Chapter 8",
+										StartOffsetMs = 700000,
+										StartOffsetSec = 700,
+										LengthMs = 100000,
+									},
+								}
+							}
+						}
+					}
+				};
+
+			var flatChapters = DownloadDecryptBook.getChapters(hierarchicalChapters).OrderBy(c => c.StartOffsetMs).ToArray();
+
+			flatChapters.Length.Should().Be(flatChapters.Length);
+
+			for (int i = 0; i < flatChapters.Length; i++)
+			{
+				flatChapters[i].Title.Should().Be(expected[i].Title);
+				flatChapters[i].StartOffsetMs.Should().Be(expected[i].StartOffsetMs);
+				flatChapters[i].StartOffsetSec.Should().Be(expected[i].StartOffsetSec);
+				flatChapters[i].LengthMs.Should().Be(expected[i].LengthMs);
+				flatChapters[i].Chapters.Should().BeNull();
+			}
+		}
+	}
+}