You're running around the Presidium Commons, trying to play hero, and you overhear a stressed-out Volus. He’s talking about a lost religious text. Suddenly, your journal updates with Irune: Book of Plenix. You check your galaxy map. Nothing. You check again. Still nothing.
It's one of those classic Mass Effect 3 frustrations. The game gives you a quest, but the solar system doesn't actually exist on your map yet. Honestly, it’s enough to make you want to throw your omni-tool at the wall.
The Book of Plenix: What It Actually Is
In the world of the Volus, the Book of Plenix isn't just some dusty old novel. It’s their version of a moral compass. Think of it like a mix between a religious text and an economic manifesto. The Volus believe in something called "Plenix," which is basically spiritual currency. You do good deeds? You earn Plenix. You act like a jerk? You lose it.
The book contains the "Twelve Acts," which are basically rules for how to live. When the Reapers hit Irune, the Volus started losing hope. They felt like they’d lost their culture along with their planet. Finding this book isn't just about ticking a box in your quest log; it’s about giving a broken species a reason to keep fighting.
Where to find it (and why you can't see it yet)
Here is the part that trips everyone up. You get the quest early—usually after Priority: Palaven. But you can’t actually finish it until much later.
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- The Location: You need to head to the Aethon Cluster.
- The System: Inside that cluster, look for the Aru System.
- The Planet: Scan the planet Irune.
If you don't see the Aethon Cluster on your map, don't panic. You haven't hit a bug. The cluster doesn't unlock until you finish Priority: Tuchanka. Some players even report it not showing up until after Priority: Citadel II (the Cerberus coup). Basically, if it’s not there, just keep playing the main story. It’ll pop eventually.
How to Complete the Mission
Once you finally have access to the Aru system, fly the Normandy over there. You’ll need to ping the planet Irune. Once the scanner picks up the artifact, launch a probe. You’ve got the book.
Now, take it back to the Citadel. You’re looking for a Volus often nicknamed the "Angry Accountant." He’s hanging out in the Presidium Commons, specifically near the bank area and the Elkoss Combine Arsenal kiosk.
What do you get for it?
Is it worth the fuel? Probably.
- War Assets: You get an update to the Citadel Defense Force. It’s not a massive boost, but every bit helps when you’re trying to stop a galaxy-wide extinction event.
- Experience: A small chunk of XP.
- Reputation: You get some Paragon/Renegade points depending on how you handle things.
The "I Can't Talk to the Volus" Bug
There’s a known issue where, even after you have the book, you can't interact with the Volus to turn it in. This usually happens if you try to do it while the Citadel is "busy" with other story events. If he won't talk to you, try leaving the floor and coming back. If that doesn't work, finish the next major story mission and try again.
Sometimes the game gets "stuck" if you have too many active Citadel fetch quests. Just keep checking back. He’s not going anywhere.
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Why this tiny quest matters for your ending
Mass Effect 3 is a numbers game. You need a high Total Military Strength to get the best possible endings. While the Book of Plenix only provides a modest bump to the Citadel Defense Force, these "Search and Rescue" missions add up.
If you’re the type of player who wants the "perfect" ending where Shepard survives or the galaxy isn't totally trashed, you can't afford to skip these. Plus, the lore is actually kinda cool. It’s one of the few times we get a real look into Volus culture beyond them just being "the short guys in suits who like money."
Summary of Actionable Steps
- Don't stress the map: If the Aethon Cluster isn't there, finish the Tuchanka story arc.
- Scan Irune: It’s in the Aru system. You don't need to land; just probe it.
- Check the Commons: Return the book to the Volus near the bank.
- Check the Spectre Terminal: If you somehow miss the book during your travels and the system becomes locked or the game progresses too far, check the Spectre Requisitions terminal. Sometimes, "missed" items show up there for purchase so you can still finish the quest.
Basically, pick it up, wait for the story to progress, scan the planet, and hand it over. It's a simple fetch quest, but in a game where the stakes are this high, every little bit of "spiritual currency" helps.
Actionable Insight: Before heading to the Aethon Cluster, make sure you have a full tank of fuel. The cluster has multiple systems (like Nura and Esori) that contain other valuable War Assets, such as the Volus Dreadnought Kwunu and Volus Intelligence Archives. Scanning everything in one trip will save you multiple trips back to the Citadel.