If you love high-stakes military science fiction, witty banter, and ancient, god-complex-addled alien AIs shaped like beer cans, Craig Alanson’s Expeditionary Force is your next favorite space opera. Following the adventures of U.S. Army Specialist Joe Bishop and his hilarious, sarcastic Elder AI sidekick, Skippy, this series has captured the hearts of readers and audiobook listeners worldwide.
Because the series spans multiple main novels, novellas, audio dramas, and a spin-off subseries (Mavericks) that directly intertwines with the main plot, tackling the books strictly by their volume numbers can lead to confusion. Reading the spin-offs out of order will spoil major plot twists, while skipping them entirely leaves massive gaps in the narrative. To help you navigate this massive universe, here is the official, author-recommended reading order.
The Recommended Expeditionary Force Reading Order
To get the absolute best experience out of the story, you should read the main series, novellas, and spin-offs in a blended order. The author, Craig Alanson, has specified this exact sequence as the official path to avoid spoilers and maintain narrative continuity:
- Columbus Day (Book 1) – The starting point. Earth is caught in a galactic war between alien factions, and Joe Bishop meets the ancient AI, Skippy.
- SpecOps (Book 2) – The Merry Band of Pirates takes to the stars on the commandeered starship Flying Dutchman.
- Paradise (Book 3) – The action shifts as the crew deals with the complicated politics and threats of the planet Paradise.
- Trouble on Paradise (Book 3.5 Novella) – A crucial side story focusing on the struggle of the UN forces and Ruhar left behind on Paradise.
- Black Ops (Book 4) – Joe and the crew embark on increasingly dangerous covert operations across the galaxy.
- Zero Hour (Book 5) – High-stakes missions put Earth in direct peril, forcing the crew to make impossible choices.
- Mavericks (Book 6) – Introduces the Mavericks alien peacekeeping force, setting the stage for the spin-off series.
- Renegades (Book 7) – The crew seeks new allies while the Mavericks deal with their own challenges.
- Deathtrap (Mavericks Book 1) – This spin-off novel takes place concurrently and must be read after Renegades to understand the evolving galactic landscape.
- Homefront (Book 7.5 Audio Drama) – Originally released as a full-cast audio drama, this is a vital bridge chapter that sets up the events of Book 8.
- Armageddon (Book 8) – The main series resumes with the fallout of the events in Homefront.
- Valkyrie (Book 9) – Joe and Skippy face devastating choices as the threat to Earth escalates.
- Freefall (Mavericks Book 2) – The second Mavericks spin-off book, which should be read immediately after Valkyrie to keep up with side characters.
- Critical Mass (Book 10) – The main narrative and the Mavericks' storylines collide in a spectacular, action-packed fusion.
- Brushfire (Book 11) – The crew deals with the immediate, world-shaking aftermath of Critical Mass.
- Breakaway (Book 12) – The scope of the conflict widens as galactic empires begin to fracture.
- Fallout (Book 13) – Long-running mysteries about the Elders and ancient alien tech begin to come to light.
- Match Game (Book 14) – Joe and Skippy engage in a high-risk game of bluffing against far superior alien forces.
- Failure Mode (Book 15) – Originally planned as the series finale, this action-packed novel wraps up many of the primary plot arcs.
- Aftermath (Book 16) – The continuation of the saga as Craig Alanson decided to extend the story to resolve remaining galactic mysteries.
- Task Force Hammer (Book 17) – The crew takes the fight directly to the galaxy's most powerful entities.
- Gateway (Book 18) – Published in 2025, this book follows the escalating galactic stakes.
- Ground State (Book 19) – Released in early 2026, continuing the intense push toward the grand finale.
Understanding the Spin-offs and Side Stories
While some readers might be tempted to skip the novellas and the Mavericks books to rush through the main numbered novels, doing so is highly discouraged. Here is why these side projects are so important to the overarching plot:
- Trouble on Paradise (Book 3.5): This novella fills in the gaps of what happened on the planet Paradise while the Flying Dutchman was away. The characters and situations introduced here return in later books.
- The Mavericks Subseries (Deathtrap and Freefall): These novels follow a separate group of human soldiers and alien allies who are operating under the thumb of the alien coalition. They provide necessary world-building and introduce key characters who join the main crew in Critical Mass.
- Homefront (Book 7.5): This audio drama features a full cast. Because of its format, some print-only readers skipped it, only to be deeply confused at the start of Armageddon (Book 8), which begins immediately after the dramatic events of Homefront. A script version is available for those who prefer reading over listening.
What to Know Before You Start
Before you dive headfirst into Columbus Day, here are a few practical tips to help you get the most out of your reading experience:
Audiobook vs. Print: While the print books are fantastic, the Expeditionary Force series is a legendary phenomenon in the audiobook community. Narrator R.C. Bray delivers an award-nominated performance, giving Skippy a hilarious, arrogant, and distinct voice that has defined the character for millions of fans. If you enjoy audiobooks, this is widely considered the absolute best way to experience the series.
A Note on "Walkiria": Some book databases and listing sites include an entry titled Walkiria published around 2022. Readers should note that this is not a separate or new book in the series; it is simply the Polish translation of Valkyrie (Book 9). You do not need to hunt down a separate book by this name.
The Final Destination: Craig Alanson has officially announced that the main Expeditionary Force series will conclude with Book 20. With Book 18 (Gateway) and Book 19 (Ground State) already published, the stage is set for the epic final installment of Joe and Skippy's journey.