diff --git a/Cargo.lock b/Cargo.lock
index d03c550..b6c789d 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -2,6 +2,15 @@
 # It is not intended for manual editing.
 version = 3
 
+[[package]]
+name = "aho-corasick"
+version = "1.1.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8e60d3430d3a69478ad0993f19238d2df97c507009a52b3c10addcd7f6bcb916"
+dependencies = [
+ "memchr",
+]
+
 [[package]]
 name = "anstream"
 version = "0.6.11"
@@ -63,6 +72,9 @@ dependencies = [
  "anyhow",
  "clap",
  "mp4",
+ "pretty_assertions",
+ "regex",
+ "rstest",
  "taglib",
 ]
 
@@ -84,6 +96,12 @@ version = "1.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "89b2fd2a0dcf38d7971e2194b6b6eebab45ae01067456a7fd93d5547a61b70be"
 
+[[package]]
+name = "cfg-if"
+version = "1.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "baf1de4339761588bc0619e3cbc0120ee582ebb74b53b4efbf79117bd2da40fd"
+
 [[package]]
 name = "clap"
 version = "4.4.18"
@@ -130,12 +148,141 @@ version = "1.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "acbf1af155f9b9ef647e42cdc158db4b64a1b61f743629225fde6f3e0be2a7c7"
 
+[[package]]
+name = "diff"
+version = "0.1.13"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "56254986775e3233ffa9c4d7d3faaf6d36a2c09d30b20687e9f88bc8bafc16c8"
+
+[[package]]
+name = "equivalent"
+version = "1.0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5443807d6dff69373d433ab9ef5378ad8df50ca6298caf15de6e52e24aaf54d5"
+
+[[package]]
+name = "futures"
+version = "0.3.30"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "645c6916888f6cb6350d2550b80fb63e734897a8498abe35cfb732b6487804b0"
+dependencies = [
+ "futures-channel",
+ "futures-core",
+ "futures-executor",
+ "futures-io",
+ "futures-sink",
+ "futures-task",
+ "futures-util",
+]
+
+[[package]]
+name = "futures-channel"
+version = "0.3.30"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "eac8f7d7865dcb88bd4373ab671c8cf4508703796caa2b1985a9ca867b3fcb78"
+dependencies = [
+ "futures-core",
+ "futures-sink",
+]
+
+[[package]]
+name = "futures-core"
+version = "0.3.30"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "dfc6580bb841c5a68e9ef15c77ccc837b40a7504914d52e47b8b0e9bbda25a1d"
+
+[[package]]
+name = "futures-executor"
+version = "0.3.30"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a576fc72ae164fca6b9db127eaa9a9dda0d61316034f33a0a0d4eda41f02b01d"
+dependencies = [
+ "futures-core",
+ "futures-task",
+ "futures-util",
+]
+
+[[package]]
+name = "futures-io"
+version = "0.3.30"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a44623e20b9681a318efdd71c299b6b222ed6f231972bfe2f224ebad6311f0c1"
+
+[[package]]
+name = "futures-macro"
+version = "0.3.30"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "87750cf4b7a4c0625b1529e4c543c2182106e4dedc60a2a6455e00d212c489ac"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
+[[package]]
+name = "futures-sink"
+version = "0.3.30"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9fb8e00e87438d937621c1c6269e53f536c14d3fbd6a042bb24879e57d474fb5"
+
+[[package]]
+name = "futures-task"
+version = "0.3.30"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "38d84fa142264698cdce1a9f9172cf383a0c82de1bddcf3092901442c4097004"
+
+[[package]]
+name = "futures-timer"
+version = "3.0.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f288b0a4f20f9a56b5d1da57e2227c661b7b16168e2f72365f57b63326e29b24"
+
+[[package]]
+name = "futures-util"
+version = "0.3.30"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3d6401deb83407ab3da39eba7e33987a73c3df0c82b4bb5813ee871c19c41d48"
+dependencies = [
+ "futures-channel",
+ "futures-core",
+ "futures-io",
+ "futures-macro",
+ "futures-sink",
+ "futures-task",
+ "memchr",
+ "pin-project-lite",
+ "pin-utils",
+ "slab",
+]
+
+[[package]]
+name = "glob"
+version = "0.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d2fabcfbdc87f4758337ca535fb41a6d701b65693ce38287d856d1674551ec9b"
+
+[[package]]
+name = "hashbrown"
+version = "0.14.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e5274423e17b7c9fc20b6e7e208532f9b19825d82dfd615708b70edd83df41f1"
+
 [[package]]
 name = "heck"
 version = "0.4.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "95505c38b4572b2d910cecb0281560f54b440a19336cbbcb27bf6ce6adc6f5a8"
 
+[[package]]
+name = "indexmap"
+version = "2.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "68b900aa2f7301e21c36462b170ee99994de34dff39a4a6a528e80e7376d07e5"
+dependencies = [
+ "equivalent",
+ "hashbrown",
+]
+
 [[package]]
 name = "itoa"
 version = "1.0.9"
@@ -148,6 +295,12 @@ version = "0.2.147"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b4668fb0ea861c1df094127ac5f1da3409a82116a4ba74fca2e58ef927159bb3"
 
+[[package]]
+name = "memchr"
+version = "2.7.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "78ca9ab1a0babb1e7d5695e3530886289c18cf2f87ec19a575a0abdce112e3a3"
+
 [[package]]
 name = "mp4"
 version = "0.14.0"
@@ -205,6 +358,37 @@ dependencies = [
  "autocfg",
 ]
 
+[[package]]
+name = "pin-project-lite"
+version = "0.2.14"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bda66fc9667c18cb2758a2ac84d1167245054bcf85d5d1aaa6923f45801bdd02"
+
+[[package]]
+name = "pin-utils"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8b870d8c151b6f2fb93e84a13146138f05d02ed11c7e7c54f8826aaaf7c9f184"
+
+[[package]]
+name = "pretty_assertions"
+version = "1.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3ae130e2f271fbc2ac3a40fb1d07180839cdbbe443c7a27e1e3c13c5cac0116d"
+dependencies = [
+ "diff",
+ "yansi",
+]
+
+[[package]]
+name = "proc-macro-crate"
+version = "3.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8ecf48c7ca261d60b74ab1a7b20da18bede46776b2e55535cb958eb595c5fa7b"
+dependencies = [
+ "toml_edit",
+]
+
 [[package]]
 name = "proc-macro2"
 version = "1.0.66"
@@ -223,12 +407,92 @@ dependencies = [
  "proc-macro2",
 ]
 
+[[package]]
+name = "regex"
+version = "1.10.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4219d74c6b67a3654a9fbebc4b419e22126d13d2f3c4a07ee0cb61ff79a79619"
+dependencies = [
+ "aho-corasick",
+ "memchr",
+ "regex-automata",
+ "regex-syntax",
+]
+
+[[package]]
+name = "regex-automata"
+version = "0.4.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "38caf58cc5ef2fed281f89292ef23f6365465ed9a41b7a7754eb4e26496c92df"
+dependencies = [
+ "aho-corasick",
+ "memchr",
+ "regex-syntax",
+]
+
+[[package]]
+name = "regex-syntax"
+version = "0.8.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7a66a03ae7c801facd77a29370b4faec201768915ac14a721ba36f20bc9c209b"
+
+[[package]]
+name = "relative-path"
+version = "1.9.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ba39f3699c378cd8970968dcbff9c43159ea4cfbd88d43c00b22f2ef10a435d2"
+
+[[package]]
+name = "rstest"
+version = "0.22.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7b423f0e62bdd61734b67cd21ff50871dfaeb9cc74f869dcd6af974fbcb19936"
+dependencies = [
+ "futures",
+ "futures-timer",
+ "rstest_macros",
+ "rustc_version",
+]
+
+[[package]]
+name = "rstest_macros"
+version = "0.22.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c5e1711e7d14f74b12a58411c542185ef7fb7f2e7f8ee6e2940a883628522b42"
+dependencies = [
+ "cfg-if",
+ "glob",
+ "proc-macro-crate",
+ "proc-macro2",
+ "quote",
+ "regex",
+ "relative-path",
+ "rustc_version",
+ "syn",
+ "unicode-ident",
+]
+
+[[package]]
+name = "rustc_version"
+version = "0.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cfcb3a22ef46e85b45de6ee7e79d063319ebb6594faafcf1c225ea92ab6e9b92"
+dependencies = [
+ "semver",
+]
+
 [[package]]
 name = "ryu"
 version = "1.0.15"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "1ad4cc8da4ef723ed60bced201181d83791ad433213d8c24efffda1eec85d741"
 
+[[package]]
+name = "semver"
+version = "1.0.23"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "61697e0a1c7e512e84a621326239844a24d8207b4669b41bc18b32ea5cbf988b"
+
 [[package]]
 name = "serde"
 version = "1.0.188"
@@ -260,6 +524,15 @@ dependencies = [
  "serde",
 ]
 
+[[package]]
+name = "slab"
+version = "0.4.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8f92a496fb766b417c996b9c5e57daf2f7ad3b0bebe1ccfca4856390e3d3bb67"
+dependencies = [
+ "autocfg",
+]
+
 [[package]]
 name = "strsim"
 version = "0.10.0"
@@ -316,6 +589,23 @@ dependencies = [
  "syn",
 ]
 
+[[package]]
+name = "toml_datetime"
+version = "0.6.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0dd7358ecb8fc2f8d014bf86f6f638ce72ba252a2c3a2572f2a795f1d23efb41"
+
+[[package]]
+name = "toml_edit"
+version = "0.22.22"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4ae48d6208a266e853d946088ed816055e556cc6028c5e8e2b84d9fa5dd7c7f5"
+dependencies = [
+ "indexmap",
+ "toml_datetime",
+ "winnow",
+]
+
 [[package]]
 name = "unicode-ident"
 version = "1.0.11"
@@ -393,3 +683,18 @@ name = "windows_x86_64_msvc"
 version = "0.52.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "dff9641d1cd4be8d1a070daf9e3773c5f67e78b4d9d42263020c057706765c04"
+
+[[package]]
+name = "winnow"
+version = "0.6.19"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c52ac009d615e79296318c1bcce2d422aaca15ad08515e344feeda07df67a587"
+dependencies = [
+ "memchr",
+]
+
+[[package]]
+name = "yansi"
+version = "1.0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cfe53a6657fd280eaa890a3bc59152892ffa3e30101319d168b781ed6529b049"
diff --git a/Cargo.toml b/Cargo.toml
index 54b3784..3e7d2cb 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -6,7 +6,12 @@ edition = "2021"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
+anyhow = "1.0.75"
 clap = { version = "4.4", features = ["derive", "cargo"] }
 mp4 = "0.14.0"
+regex = "1.10"
 taglib = "1.0.0"
-anyhow = "1.0.75"
+
+[dev-dependencies]
+pretty_assertions = "1.4"
+rstest = "0.22"
diff --git a/src/main.rs b/src/main.rs
index 2757203..b7cc25a 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,3 +1,8 @@
+//
+
+#[cfg(test)]
+mod tests;
+
 use anyhow::{Context, Result};
 use clap::{crate_version, Parser};
 use std::{
@@ -44,7 +49,8 @@ fn main() {
 fn rename_files_in_directory(directory: String, args: &Arguments) {
     println!("Renaming files in {}", directory);
     match rename_files(&directory, &directory, args) {
-        Ok(count) => println!("Renamed {} files", count),
+        Ok(count) if args.not_dry_run() => println!("Renamed {} files", count),
+        Ok(_) => println!("Dry-Run complete"),
         Err(e) => eprintln!("Error: {}", e),
     }
 }
@@ -60,43 +66,72 @@ fn rename_files(directory: &str, base: &str, args: &Arguments) -> Result<i32> {
                 count += rename_files(sub_dir, base, args).context("Failed to rename files")?;
             }
         }
-        if path.is_file() {
-            if let Ok(file) = taglib::File::new(&path) {
-                if let Ok(tag) = file.tag() {
-                    if let Some(title) = tag.title() {
-                        if let Some(artist) = tag.artist() {
-                            let album = parse_album(&title);
-                            count += 1;
-                            let new_name = match album.len() {
-                                0 => format!("{artist}/{title}/{title}.m4b"),
-                                _ => format!("{artist}/{album}/{title}/{title}.m4b"),
-                            };
-                            println!("Renaming {} to {}", path.display(), new_name);
-                            let target_path = Path::new(&base).join(new_name);
-                            if !target_path.exists() {
-                                let dir = target_path.parent().with_context(|| {
-                                    format!("Failed to get parent: {:#?}", target_path)
-                                })?;
-                                if args.not_dry_run() {
-                                    create_dir_all(dir).with_context(|| {
-                                        format!("Failed to create directory: {:#?}", dir)
-                                    })?;
-                                }
-                            }
-                            if args.not_dry_run() {
-                                rename(&path, &target_path).with_context(|| {
-                                    format!("Failed to rename file: {:#?}", target_path)
-                                })?;
-                            }
-                        }
-                    }
-                }
+        if !path.is_file() {
+            continue;
+        }
+        let Ok(file) = taglib::File::new(&path) else {
+            continue;
+        };
+        let Ok(tag) = file.tag() else {
+            continue;
+        };
+        let (Some(title), Some(artist)) = (tag.title(), tag.artist()) else {
+            continue;
+        };
+        let album = parse_album(&title);
+        count += 1;
+        let new_name = if album.is_empty() {
+            format!("{artist}/{title}/{title}.m4b")
+        } else {
+            build_series_name(&artist, &album, &title)
+        };
+        println!("==============================");
+        println!("- artist: {artist}");
+        println!("- album : {album}");
+        println!("- title : {title}");
+        println!("> {new_name}");
+        if args.not_dry_run() {
+            let target_path = Path::new(&base).join(new_name);
+            if !target_path.exists() {
+                let dir = target_path
+                    .parent()
+                    .with_context(|| format!("Failed to get parent: {:#?}", target_path))?;
+                create_dir_all(dir)
+                    .with_context(|| format!("Failed to create directory: {:#?}", dir))?;
             }
+
+            rename(&path, &target_path)
+                .with_context(|| format!("Failed to rename file: {:#?}", target_path))?;
         }
     }
     Ok(count)
 }
 
+fn build_series_name(artist: &str, album: &str, title: &str) -> String {
+    let index = parse_index(title);
+    let title = parse_title(title);
+    format!("{artist}/{album}/{index}. {title}/{index}. {title}.m4b")
+}
+
+fn parse_index(title: &str) -> String {
+    if let Ok(index_re) = regex::Regex::new(r", Book (?P<INDEX>\d+)") {
+        if let Some(captures) = index_re.captures(title) {
+            let index = captures.name("INDEX").map_or("", |m| m.as_str());
+            return index.to_string();
+        }
+    }
+    String::new()
+}
+fn parse_title(title: &str) -> String {
+    if let Ok(title_re) = regex::Regex::new(r"^(?P<TITLE>.*?):") {
+        if let Some(captures) = title_re.captures(title) {
+            let title = captures.name("TITLE").map_or("", |m| m.as_str());
+            return title.to_string();
+        }
+    }
+    title.to_string()
+}
+
 fn parse_album(title: &str) -> String {
     let parts: Vec<&str> = title.split(':').collect();
     match &parts[..] {
diff --git a/src/tests.rs b/src/tests.rs
new file mode 100644
index 0000000..2f59c16
--- /dev/null
+++ b/src/tests.rs
@@ -0,0 +1,18 @@
+//
+use super::*;
+
+use pretty_assertions::assert_eq;
+
+#[rstest::rstest]
+#[case("Discworld", "The Truth: Discworld, Book 25", "25. The Truth")]
+#[case(
+    "A Darker Shade of Magic",
+    "A Conjuring of Light: A Darker Shade of Magic, Book 3",
+    "3. A Conjuring of Light"
+)]
+fn parse_series_details(#[case] album: &str, #[case] title: &str, #[case] expected: &str) {
+    let expected_result = format!("Bob/{album}/{expected}/{expected}.m4b");
+    let result = build_series_name("Bob", album, title);
+
+    assert_eq!(result, expected_result);
+}