Unsurprisingly, more than a dozen villains who have appeared throughout the MCU have been showcased in prison. Some of the characters who have been featured behind bars are well-known supervillains like Loki and Kingpin, but others, such as Kurse from Thor: The Dark World, are a bit more obscure.
Most of these villains have been shown in captivity based on what they have done in specific movies or TV shows, but a few spent time in jail prior to appearing on-screen. Shockingly (and ironically), the number of MCU villains who have been in prison in the franchise is the same as the number of superheroes who have been showcased in the same manner.
Every MCU Villain Who Has Been in Prison
Kurse
Kurse was an antagonist in Thor: The Dark World. He let himself get captured by Asgardians in order to infiltrate the prisons and stage a break, which he successfully did. Kurse didn't spend a lot of time in prison, and, as mentioned, he got himself captured on purpose, but he did technically serve some time.
Loki
Loki is another character who has spent a lot of time in prison throughout the MCU. After he got involved with Thanos and orchestrated the Battle of New York in The Avengers, he was formally imprisoned on Asgard for his actions. However, before even that, he was technically imprisoned on Nick Fury's helicarrier during the events of The Avengers after he was briefly captured in Germany.
Thor eventually released Loki from prison in Asgard, but he found himself behind bars once again in the Loki series when he was put in prison by the TVA (Time Variance Authority).
Helmut Zemo
Helmut Zemo was imprisoned twice in the MCU. Captain America: Civil War revealed that Zemo was behind Bucky Barnes' brainwashing and the bombing of the United Nations meeting that killed Wakanda's King T'Chaka. Following the events of Civil War, Zemo was convicted of his crimes and sent to prison.
However, he was broken out by Bucky Barnes in The Falcon and the Winter Soldier, but he was then arrested again and sent to the Raft.
Wilson Fisk
Vincent D'Onofrio's Wilson Fisk was put in prison multiple times in the original Daredevil series, as he was an extremely dangerous and prominent criminal. However, after the Snap, Fisk was able to return to power outside of prison and is now the mayor of New York City, which is being further explored in Daredevil: Born Again Season 2.
Benjamin Poindexter
Benjamin Poindexter (aka Bullseye) was thrown in prison for the murder of Foggy Nelson and was forced to serve a life sentence. He spent much of Daredevil: Born Again Season 1 in prison, but got out near the end of the installment.
Born Again wasn't the only time fans saw Poindexter behind bars, though. Daredevil Season 3 depicted the character in custody.
Thaddeus Ross
Thaddeus Ross is another character who served some time in the MCU. He became imprisoned on the Raft in Captain America: Brave New World, which is ironic considering he put a lot of past MCU heroes on the Raft for violating the Sokovia Accords.
Specifically, Ross was detained following his transformation into Red Hulk at the White House, and for all of the destruction he caused. He voluntarily stepped down as president and turned himself in.
Samuel Sterns
After the events of The Incredible Hulk, Samuel Sterns (aka the Leader) was taken into custody by SHIELD and placed in a secret location called Camp Echo One. No one heard from Sterns since The Incredible Hulk, but he popped back up again in Captain America: Brave New World.
However, at the end of that movie, after Sterns was apprehended again, he was sent to the Raft alongside Thaddeus Ross.
Emil Blonsky
Emil Blonsky has appeared in multiple MCU projects and has been put in prison multiple times. After his introduction in The Incredible Hulk, Blonsky was sent to a cryo-cell in Alaska called the Vault. Later on, Blonsky was sent to the Department of Damage Control (which will have a heavy presence in Spider-Man: Brand New Day).
After some time, he was eventually granted parole. However, he was sent back to prison after violating his parole when he turned into Abomination.
Najma
In Ms. Marvel, Najma and the Clandestines were captured by the Department of Damage Control (DODC) and imprisoned in the DODC supermax prison in California. Their stint behind bars didn't last long, though, as they escaped captivity. By the end of the series, Najma didn't return to prison, as she sacrificed herself in order to close the veil to the Noor Dimension.
Kamran
Najma's son, Kamran, was captured by the DODC in Ms. Marvel and put in prison with the rest of the Clandestines. However, when they all escaped, Najma left him behind because he betrayed them. He still fled the prison, but ended up in Jersey City with Bruno Carrelli.
Trevor Slattery
Trevor Slattery was first arrested in Iron Man 3 for being the spokesperson for Aldrich Killian. He was sent to Seagate Penitentiary for many years, but was then broken out by the Ten Rings, as they weren't happy that he impersonated the Mandarin.
After the Ten Rings took Slattery, they kept him as a prisoner under their watch. He wasn't technically in government confinement at that time, but was still living like a prisoner. Slattery was then imprisoned once again by the DODC, before being broken out by newfound friend Simon Williams.
Justin Hammer
Justin Hammer has somewhat of a cult following in the MCU fandom, and many want to see him return to the franchise in Avengers: Doomsday or Armor Wars, if that project is ever released. After his partnership with Ivan Vanko in Iron Man 2 and his crimes connected to the Stark Expo attack, Hammer was sent to Seagate, the same prison Trevor Slattery was at.
No updates have been given about Hammer's status in the MCU. The last time he was seen was in the Hail to the King one-shot that was released, which confirmed he was still an inmate.
High Evolutionary
The High Evolutionary was the main antagonist of Guardians of the Galaxy Vol. 3, and was eventually defeated by the Guardians at the end of the film. The theatrical cut of the movie made it seem that the High Evolutionary may have died after his ship exploded. However, a deleted scene revealed that he got locked up on Knowhere following his defeat.
It is also worth noting that director James Gunn confirmed that the High Evolutionary survived, so that deleted scene of him being sent to prison is most likely canon.
Adrian Toomes
After he fully turned into Vulture and terrorized Peter Parker in Spider-Man: Homecoming, Adrian Toomes was sent to a DODC facility at the end of that film. One of the movie's post-credits scenes confirmed that he was locked up inside, as it featured Toomes conversing with Scorpion.
Scorpion
As mentioned, Scorpion spent time in prison during Spider-Man: Homecoming, as he was locked up alongside Adrian Toomes in a DODC facility. However, Scorpion will be getting out in Spider-Man: Brand New Day, as set photos have showcased actor Michael Mando filming scenes outside.
