Want to learn more Alexei Navalny, the high-profile critic of Russian President Vladimir Putin who reportedly has died in a maximum-security prison? There's an Oscar-winning documentary about him.

Navalny, 47, who had been imprisoned since 2021, died at a remote prison colony called "Polar Wolf," located about 40 miles north of the Arctic Circle, the country's state media reported Friday. No official cause of death was given.

Officials said he "felt unwell" after going for a walk and "almost immediately lost consciousness." Attempts to resuscitate him failed. Kremlin spokesman Dmitry Peskov said he had no information about Navalny's death.

Navalny had been under arrest since January 2021 when he returned to Russia after spending five months in Germany recovering from a poisoning he blamed on the Kremlin.

Who was Alexei Navalny?:What to know about Putin's top critic who died in prison.

What is the documentary "Navalny" about?

The 90-minute film, "Navalny," debuted in January 2022 at the virtually-held Sundance Film Festival. The film documents his career of combating Russian corruption – he was prevented from opposing Putin in the 2018 presidential election – and Navalny's recovery from an August 2020 near-fatal attempt on his life when he was poisoned by the nerve agent, Novichok.

"Navalny" won two awards at Sundance including the audience-voted festival favorite award and won the Oscar for best documentary in 2023.

The film's flashback to the poisoning "could be the most sickening and calamitous suspense-thriller episode you ever saw, with Navalny first feeling the symptoms on a plane," wrote Owen Gleiberman in Variety. In Navalny's cell-phone video, "his cries of agony sound barely human," he wrote.

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Then, we see Navalny's wife Yulia struggle to get Navalny out of the Russian hospital; German chancellor Angela Merkel sends an ambulance plane to retrieve him and he recovers in Berlin. Amid the recovery, he investigates the poisoning and a member of the team who tried to kill him to admit it during a phone call. The film follows Navalny's arrest on his return to Moscow in January 2021. Since then, the dissident has been held in custody for charges related to extremism and fraud, but many considered him a political prisoner being punished for his opposition to Putin and the Kremlin.

How to watch 'Navalny,' a documentary about the Putin critic

CNN and CNN International will air the documentary "Navalny" on Saturday, Feb. 17, at 9 p.m. EST/6 p.m. PST.

You can also watch "Navalny" anytime on the Max streaming service, which formed in May 2023 from the merging of HBO Max and Discovery+. If you subscribe to a pay TV service with HBO, you likely already have a subscription (go to the Max help center to find out). You can watch Max on many devices including smart TVs, smartphones and tablets, streaming devices such as Amazon Fire TV, Apple TV, Roku, and video game consoles.

Subscription costs start at $9.99 monthly or $99.99 annually for the service with ads. You can also subscribe to one of two advertising-free tiers:

• Ad-Free ($15.99/month or $149.99/year); Stream in high-def on two devices and get 30 downloads to watch on the go.
• Ultimate Ad-Free ($19.99/month or $199.99/year): Stream on four devices simultaneously, some in 4K UHD video with Dolby Atmos sound; up to 100 downloads.

The film can also be streamed on the CNN app if you are a pay-TV subscriber. "Navalny," from CNN Films and HBO Max, was made in association with Fishbowl Films, RaeFilm Studios, and Cottage M.

Contributing: Kim Hjelmgaard, Amanda Lee Myers and Brian Truitt.

Follow Mike Snider on X and Threads: @mikesnider & mikegsnider.

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