Mr Bates vs The Post Office has received largely positive reviews from critics following the first episode airing on New Year's Day.
The ITV drama is based on the real-life story of postmaster Alan Bates (Toby Jones) who drove the campaign to expose the Post Office Horizon IT scandal.
The Telegraph described it as "undeniably powerful and finally redemptive".
But the Independent said the series "could use a bit more drama".
The four-part mini-series, which is being aired nightly on ITV this week, focuses on the epic legal battle Bates led and won, paving the way for dozens of convictions to be overturned.
Awarding the first episode four stars, the Telegraph's Jasper Rees wrote: "Fuelled by righteous rage and sheer incredulity at a corporate malfeasance that can never be fully explained, it's undeniably powerful and finally redemptive.
"'We just cling to a notion, don't we,' someone says, 'that people can't be that bad.' I've rarely felt more manipulated by a drama, and rarely resented it less," he added.
The Guardian's Rebecca Nicholson also considered the series worthy of four stars, despite feeling it was a little overblown on occasion.
"The drama plays out like an episode of Black Mirror at first, and it is easily as harrowing as the bleakest of those imagined dystopias," she said.
"If the drama can be a little broad-brushstrokes at times, with significant moments delivered as if in bold capital letters, you can't really blame it. The moments of triumph are so hard-earned that it seems only fair to drench them in swelling strings."
Carol Midgley of the Times also awarded the series four stars. "The Post Office Horizon scandal is a story so incensing, outrageous and downright ugly that I found it difficult to watch," she said.
"Seeing decent, ordinary, innocent people being mentally tortured and systematically robbed of their livelihoods, homes, life savings, good health and reputations by corporate ruthlessness in Mr Bates vs the Post Office made me uncomfortable to the point of heartburn.
"Perhaps Hughes's biggest achievement is in making it so discomfiting to watch. It is still scarcely believable that this happened in modern Britain, that good people actually went to prison for things they hadn't done."
There was praise for the cast from the Evening Standard's Martin Robinson. "The Kafka-esque situation is thoroughly humanised by the performances", he said, adding: "Like BBC's Jimmy Saville series The Reckoning, as a watch this is both gripping and deeply disturbing.
"It it is the kind of viewing that is essential because it dramatises the effects of a scandal that has only been rendered in print."
The Independent's Nick Hilton was a little less enamoured, giving the drama three stars although he also described the cast warmly as "a fine assembly of British television actors".
"Getting into the nuts and bolts of the Horizon system, spelling out for audiences exactly what happened, isn't conducive to dramatic programming. It is hard to imagine many will stick with Mr Bates vs the Post Office for the full duration of its four-night run.
"Through odd creative decisions and the technical nature of the intrigue, Mr Bates vs the Post Office ends up being a human drama that could use a bit more drama."
