Suzanne has hallucinations while getting back on her medications. She is the first to be interviewed for a federal investigation into the riot and murders. Those found in the bunker are held in isolation at Litchfield's maximum security prison, and they face various abuses from the guards and inmates. Frieda attempts suicide, while Red confronts her roommate, Badison, to protect her family. Piper desperately tries to find Alex, and fears the worst when she learns a prisoner had died in the riot. Gloria tries to attack Maria, but they are handcuffed and forced to kiss by the guards. Taystee is visited by CO Tamika Ward, who had been her friend on the outside. Suzanne is released from questioning and is brought to the prison, which she realizes is not her "home" anymore.

Detectives are pressured to file charges on two murderers and three riot leaders within a week. Daya makes a plea agreement for Humphrey's murder, while Taystee is considered a leader as the public face of the riot. Cindy tries (and fails) to warn Taystee about the framing with a note, but when she learns their fingerprints are on Piscatella's gun, Cindy turns on Taystee to save herself. Gloria names Maria as the riot's mastermind and pressures Blanca to do the same. Despite Maria's attempts to frame Gloria, MCC corroborates Gloria's story and she gets immunity for her testimony. Piper bonds with her cellmate, Beth, but she later learns that Beth killed her children. Caputo becomes depressed while on suspension. He reconnects with Figueroa, who is now interim warden. Dixon invites himself on a road trip with Coates, not realizing that Pennsatucky is hiding in the trunk.

Linda is identified in a Cleveland prison. When she threatens to sue MCC for $10 million, she is promoted to senior vice president. Red learns of Piscatella's death during her interview, and fails to inform the others; Piper misinterprets Red's message to mean Alex was killed in the pool. Nicky is threatened with drug, theft, and distribution charges to pressure her testimony against Red. Frieda retrieves Cindy's note and fakes senility in her interview. She is transferred to B Block with the old-timers and crazies, including Suzanne. In general population, inmates learn the power structure: D Block is run by Barbara, and C Block is run by Carol, two antagonistic sisters at the head of a decades-old feud. After Daya is beaten by a guard, Daya's roommate, Daddy, gives her oxycodone. On work detail, Cindy, Flaca, Daya and Morello steal toiletries, but the products are sabotaged as an initiation.

Blake, Luschek and McCullough return to duty; McCullough is suffering from PTSD following the riot. They are invited into the fantasy inmate league, a game played by the guards where they gamble on inmate deaths and injuries. Alex returns to general population and reunites with Piper. It is revealed that Maureen was the inmate who died in the riot. Coates, Dixon and Pennsatucky spend their day at an amusement park. Aleida struggles with employment outside of prison, and she gets involved in a pyramid scheme selling dietary shakes. Taystee speaks with Caputo after learning she is being charged for Piscatella's murder. Nicky tells Red about the drug charges and gets Red's permission to testify against her.

Daddy's rat prank results in MCC losing the lucrative cheese-packaging contract and unintentionally closing the route that CO Hellman uses for smuggling. Badison seeks revenge by having her people defecate in D Block's laundry. Daddy further incites her strung-out followers by blaming C Block for cutting off their supply. Daya consoles Daddy. Luschek is made head of recreation and interviews radio show acts. Flaca looks for a co-host and finds an unexpected rapport with Cindy. Gloria fears she is entering menopause. Blanca learns that she has limited fertility. Red signs a plea agreement to inciting the riot to avoid other charges. In court, Taystee pleads guilty to inciting the riot but not guilty to murder; the ACLU offers representation for Taystee, and the Black Lives Matter movement pressures MCC into taking Taystee out of solitary. Piper proposes a prison wedding to Alex. Aleida visits her kids in foster care, but discovers that none of them want anything to do with her.

Carol holds Badison accountable for Daddy's prank that cost them their cushy job and cuts her out. Badison consults with Alex and convinces Luschek to smuggle valuable smartphones. Though Alex doesn't want to take part, she ends up with the phone when Badison is stabbed in the yard by Daddy's girls. Strung-out, Daya steals Barbara's personal stash; Daddy is incensed and they have angry sex. Taystee receives fan mail, which the guards redact. Suzanne reunites with Taystee and Cindy, but she doesn't know how to talk with them while keeping the secret. After being suspected of an attempted suicide, Maria is released from Psych with the suggestion of finding religion. Pennsatucky blackmails Linda for a bunk in B Block. Preparing to leave town, Caputo goes on his first real date with Figueroa, and tries to give her closure for a past event. Considering writing a memoir, Piper examines the library and finds old photos from before the feud. Piper determines to heal divisions by bringing back kickball.

Alex hides the cellphone through a lockdown and search. She finds more money added to her commissary, despite wanting to stay out of the gang. Gloria helps Luschek with his dance-aerobics class. Piper extorts Luschek to return kickball. Daddy asks Daya to buy drugs through her friends in C Block. Blanca, wanting a baby due to her limited fertility, provides Daya the drugs in exchange for retrieving Diablo's sperm donation from the visitation washroom. The swap is noticed and Daya is beaten by C Block inmates. However, Daya manages to save four pills for Daddy. Blanca and Nicky are surrounded by the same gang during the insemination procedure. Red schemes against Frieda and gains an alliance with Carol. Aleida is stopped from selling outside the prison by CO Hopper, who takes her out for a date. In a media interview, Taystee describes guard abuses and has her mail cut off by Tamika.

Aleida uses Hopper as an unwitting mule to bring drugs into the prison by using a false bottom of the dietary shake container, but as the weight is increased, Hopper discovers the tampering. The inmate league has seen little action since segregating the blocks, so Luschek agrees to an interblock kickball championship in the field. In warmups, Piper is confirmed as C Block captain over Badison. Gloria continues to be harassed, and is transferred to D Block with Daya and Maria. Barbara achieves 30 days of sobriety. Now with new clarity, Barbara plots to kill Carol, who she blames for spiking her drugs. Cindy makes an anonymous call to Caputo, provoking him into questioning a suspicious CERT member; Figueroa advises him to instead work the PR campaign. Frieda apologizes for misleading Suzanne and explains the block feud.

Piper, Sophia and Blanca are told they'll be released the next day - the day of the kickball championship. Piper and Alex are "prison married" by Nicky. Aleida is shocked to see Daya high on heroin, but she continues supplying her eldest to save her younger children. Taystee is found guilty. Caputo confronts a CERT member, who punches him; Figueroa sets aside business to tend Caputo's wounds. Luschek visits Gloria, who challenges him to stop the fight. Carol and Barbara meet in a closet; the war is a diversion for them to infiltrate B Block and kill Frieda. Maria has a change of heart and convinces McCullough to let the captains pick new teams, mixing the blocks. When Badison signals the attack, Suzanne kicks a high ball and the inmates are caught in the excitement of the play. With no fight causing a lockdown, Barbara and Carol's antagonism results in their deaths, bumping Copeland from last to first in fantasy inmate. Lorna goes into labor and is brought to medical in distress. Piper and Sophia are united with family members, but Blanca is taken into custody by Immigration and Customs Enforcement, for which PolyCon is running a new detention facility.