Julianne Nicholson, Jean Smart, Angourie Rice, Evan Peters, Sosie Bacon, David Denman, Neal Huff, James McArdle, Guy Pearce, Cailee Spaeny, John Douglas Thompson, and Joe Tippett appear in supporting roles.

In the fictional suburb of Easttown, Philadelphia, police detective Marianne "Mare" Sheehan investigates the recent murder of a teenage mother while trying to keep her own life from falling apart.

Mare is a local hero, having scored the winning basket in a high school basketball game that won Easttown its first state championship 25 years earlier.

Executive producers include Ingelsby, O'Connor, Kate Winslet, Paul Lee, Mark Roybal, and Gordon Gray.

[6][15][16] In January 2020, it was announced that Craig Zobel would replace O'Connor as director due to scheduling issues and also serve as executive producer.

[19] In September 2019, the cast was rounded out with Julianne Nicholson, Jean Smart, Angourie Rice, Evan Peters, Cailee Spaeny and David Denman.

[20] John Douglas Thompson, Patrick Murney, Ben Miles, Katie Kreisler, James McArdle, Sosie Bacon, Joe Tippett, Neal Huff were cast in October 2019.

In the same month, Mackenzie Lansing, Kate Arrington, Ruby Cruz, James Easter Bradford, Elisa Davis, Enid Graham, Justin Hurtt-Dunkley, Izzy King, Jack Mulhern, Anthony Norman, Drew Scheid, and Madeline Weinstein were cast.

[22][23] Filming of the show began in the fall of 2019 around suburban Philadelphia and was reported to still be in progress as of March 2020, with plans to continue through April.

The website's critics consensus reads, "Grounded by a career-best Kate Winslet, Mare of Easttown's ambitions at times exceed its reach, but its central mystery is supported by such strong sense of place and character it hardly matters.

"[36] Alex Abad-Santos of Vox described Winslet's performance as "mesmerizing", adding that "she allows us to see the ugliness Mare is capable of and how obsessive, perhaps even abusive, she can be when she's threatened.

"[40] Caryn James of the BBC wrote, "Winslet makes an unglamorous return to TV...and her fierce, ordinary heroine is gloriously real.

[43] The New York Times was dismissive in its review, with television critic Mike Hale writing: "Some style in the direction or honest feeling in the screenplay could have mitigated the dreariness, but 'Mare' doesn't offer much beyond Ben Richardson's burnished cinematography.

"[45] Critics and viewers have also particularly praised the series and Winslet for convincingly replicating the Philadelphia regional accent, an oddity in mainstream media.