Halo Season 2 Finale Shocks With the Horrific Debut of The Flood

Halo Season 2 reached its finale – and quickly pulled the rug out from under viewers with the  nightmarish reveal of The Flood! 

All season long, Halo had been explore the deeper pain and loss of the Human-Covenant War, and built up the finale episode, "Halo", to be a race between Master Chief and his Covenant rivals The Arbiter and Makee to reach the Halo ring's surface. However, the first scene of the episode revealed that another threat was emerging, even as the UNSC and Covenant forces headed for a major showdown. 

In Halo Season 2 Episode 7, Dr. Catherine Halsey (Natascha McElhone) and her daughter Miranda Keyes (Olive Gray) discovered an ancient but technologically advanced civilization under the surface of planet Onyx. Halsey found a lab where the corpse of an ancient scientist was clutching a device – a device Miranda naively took from the ancient lab and brought back to her own lab in the ONI facility on Onyx. When Halo Season 2 Episode 8 begins, Miranda is accosted by a fan-girl lab tech named Janine, who had secretly come in earlier to sneak a peek at the new discovery. Miranda begins to examine the sample and discerns that the relic she found is covered in strange dormant spores that have suddenly come alive again. The discovery is too late: Janine is already a carrier for The Flood spores, and when she quickly transforms into one of the dread parasitic monsters, it starts a chain of infection that eventually overruns the entire base. 

Halsey and ONI leader Admiral Parangosky (Shabana Azmi) are both infected by The Flood, as is Soren-066's (Bokeem Woodbine's) wife Laera (Fiona O'Shaughnessy). Soren escapes Onyx with a few allies in tow, but Miranda is left trapped in her lab, surrounded by The Flood. 

To Halo's credit, it's depiction of The Flood (at least the initial stages of infection) is pretty freaky – and in the era of HBO's The Last of Us, and The Walking Dead, that's really saying something. From the makeup and prosthetic work to the impressive ensemble acting to create The Flood's twitching movements, and unsettling scenes of hivemind coordination, The Flood add an element of tension and fear that Halo was very much in need of. It was a long wait to get here, but ultimately worth it. 

Halo's The Flood Monsters Explained

The Flood are a mutated and corrupted form of the Halo Universe's oldest race The Precursors, which infected ancient humans and created the parasitic species known as The Flood. When The Flood spread across the galaxy, another ancient race, The Forerunners ended up going to war with humanity and The Flood, building a series of super-weapons known as the Halo rings to cleanse the galaxy of life (and parasitic hosts), moving species like humanity out of range of the weapons. The history of The Flood and Precursors were wiped away by the Forerunners, until some dormant samples of The Flood kept in ancient Forerunner research facilities (and on Halo) got loose during the Human-Covenant War, threatening the galaxy all over again (as seen in the Halo video games). 

Halo Season 2 is now streaming on Paramount+