Starting Point
Yuri, who has lost their memory, wakes up aboard the Interstellar Cruiser D.Q.O. They are taken by Setsu to participate in a meeting to identify the "Gnosia," a being that attacks and annihilates humans.
Episode 1•27m
Loops
Yuri, who looped back to the first day, attends the meeting knowing who the Gnosia is. Yuri tries to cast suspicion on SQ, but the discussion doesn't progress as expected...?
Episode 2•26m
New Crew Members
Shigemichi and Stella join the group, and a meeting is held with seven people. During the meeting, Yuri uses their intuition to identify the Gnosia, but they struggle to convince the other crew members.
Episode 3•26m
Silver Key
Despite identifying the Gnosia and surviving, Yuri finds themself back at the first day in a daze, when a person with an unusual presence, Yuriko, appears before them. She seems to know something, but...?
Episode 4•24m
Wild Intuition
New crew members Comet and Chipie join the meeting. Two of the crew claim to be engineers, but Racio argues against voting for them, resulting in the votes going to...?
Episode 5•26m
Nostalgic Flowers
Yuri attends the meeting in a new role as the "Guardian Angel." With Jonas and Kukrushka joining, the meeting now has 13 people, and as the situation becomes chaotic, one crew member raises their hand.
Episode 6•26m
Understand?
Otome and Remnan join in and the meeting is about to begin, but the other new crew member, Sha-Ming, refuses to come out of his room. Meanwhile, Shigemichi begins to talk about his feelings for Stella.
Episode 7•24m
Guard Duty
Remnan and Kukrushka step forward as "Guard Duty," a role that confirms they are human. As the number of positions increases and the meeting becomes more complicated, Sha-Ming, who is suspected by Kukrushka, takes a certain action...
Episode 8•24m
World of Gnosia
Yuri awakens as a Gnosia. Though they feel hesitant about deceiving their fellow crew members, they are touched by the feelings of Comet, who shares their position, and resolve to fulfill their role as promised to Setsu.
Episode 9•25m
Citizen Slime
Yuri, who has looped once again, is astonished by their new appearance. Amidst this, the meeting is postponed due to Sha-Ming's absence, and Raqio reveals the secret of the Silver Key to the bewildered Yuri.
Episode 10•24m
511
Upon waking up, Yuri finds themself in a loop where they and SQ are on Guard Duty. Knowing that they are both human, the two grow closer, and eventually SQ reveals her true "identity"—.
Episode 11•25m
Allacosia
Gina, who intensely dislikes lying and deceiving others, is confided in about the loops by Yuri. Recalling a painful past, she expresses her fears and resistance toward becoming a Gnosia.
Episode 12•24m
Interlude
Before the meeting, Setsu loses consciousness and is taken to the Sickbay. As they share the information they have acquired, Yuri suggests that Setsu, who appears exhausted from having repeated hundreds of loops, take a break. The "Truth Arc" begins...
Episode 13•24m
15-Person Meeting
"If you survive this loop, I'll tell you everything." Yuri, presented with a condition by Yuriko, attends a meeting where all 15 crew members are gathered. However, once the meeting begins, an unexpected proposal comes from Yuriko.
Episode 14•25m
The Final Problem
Raqio, who was identified as a Gnosia by the Engineer, Yuri, claims innocence based on a certain action. The emergence of an AC Follower throws the meeting into chaos, and Yuri is cornered.
Episode 15•25m
Truth
When Yuri awakens, it's in a world line where the ship has escaped Gnosia contamination. As Yuri is bewildered by Kukrushka's implication of "the end of the universe," an alarm blares detecting an abnormal biological reaction.
Episode 16•24m
Bug
Yuri learns the truth: that they are a "Bug" that shouldn't exist. They struggle to escape the time loop and the cosmic collapse caused by their dual existence, but...?
Episode 17•24m
A World With a Future
Yuri awakens on "DAY 0," the day before the loop they always experience and before escaping Liu-An. They meet Setsu there, but Setsu seems unaware of the Silver Key or the loops...
Episode 18•27m
Epilogue
Yuri has escaped the loop, but the crew members have lost all memory of Setsu. On the planet where they land, Yuri follows Setsu's traces, only to be confronted with the harsh fact that Setsu's very existence has vanished.
Episode 19•24m
To the World of Stars
In order to end Setsu's loop, Yuri obtains Raqio's "Silver Key." As Yuri tries to host the key once again, Raqio calls out to them.
Episode 20•24m
End Point and Starting Point
Yuri reunites with Setsu on the other side of the dimensional door. They find themselves in the world line before they received the Silver Key that first awakened them. And so, their final discussion begins――
Episode 21•27m
The story of GNOSIA takes place on a ship drifting through space. Gnosia is an enemy that disguises itself as a human and attacks them. It is now on the spaceship, causing everyone onboard to be suspicious of each other. The crew decides to vote on the most suspicious-looking person every day and put them into a cold sleep. If the humans succeed in putting Gnosia to sleep, they'll win. On the other hand, if they don't, everyone on board is in danger. The right decision must be made. No matter what decision is made by the main character, Yuri, she finds herself in a time loop that returns her to the first day of the crisis. Will the crew on board make the right decision? What is the secret behind the time loop? What secrets hide behind the faces of everyone on board? GNOSIA begins now – a story of looping, fleeting moments that feels like an eternity but passes by in an instant. Have a pleasant journey. (Source: Crunchyroll)