In the detective crime drama Mare of Easttown, Kate Winslet speaks with a distinct Delco accent. The series follows former high school basketball star turned police detective Mare Sheehan (Winslet) as she investigates the murder of one young woman and the disappearance of two others in Easttown, Pennsylvania. Mare of Easttown features a standout cast that includes Jean Smart, Guy Pearce, and Evan Peters. The show's creator Brad Ingelsby managed to capture and convey the cultural authenticity of eastern Pennsylvania, including Winslet's spot-on Philadelphia accent that has become a focal point of her performance.

Ingelsby's Easttown is located in Delaware County, aka "Delco," but the real Easttown is in Chester County on the Delco border. Ingelsby, who grew up in the area, told Phillymag he chose to alter the geography because the shooting locations "really captured more of a blue-collar vibe than you get in the real Easttown." In the “Welcome to Easttown” behind-the-scenes featurette, he explains, "These are people who get up every morning and go to jobs they don't necessarily love but, yeah, they do it out of a sense of duty." Nobody feels the weight of that burden more than Mare, whose life is intertwined with both the victims, their families, and the Mare of Easttown's murder suspects. Ingelsby's determination to make a gritty, believable, small town-based crime drama meant his British leading lady had to nail the regional dialect, which according to many linguists and dialect coaches, is one of the hardest to master.

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Trying to dissect the Delco accent is a daunting task, but according to W Magazine, "The first thing to know is that Delaware County’s accent - characterized by its rounded vowels and shortened long-e and long-a sounds, perhaps most notably in the pronunciation of the word 'water' as 'wooder' - is highly specific to the Philadelphia area." According to an article in the LA Times, a Philadelphia accent is a mash-up of "rounded Os, erratic As, dropped consonants and smushed syllables." Winslet told the news outlet, “It is absolutely up there amongst the top two hardest dialects I’ve ever done,” due to Delco's variety of quirks, one of which includes running words together so that "wouldn’t and couldn’t become wuh-ent cuh-ent.” Further complicating the process is that accents can vary from person to person.

Mare Sheehan standing outside the Easttown police station

According to The Philadelphia Inquirer, to prepare for the role, Kate Winslet worked with her long-time dialect coach Susan Hegart. Winslet developed a daily routine of listening to vocal recordings of a teacher named Trish Lauria: one of 40 locals matched to the actors and their roles by local dialect coach Susanne Sulby. Winslet said the trickiest part of doing a dialect is not to try too hard. It becomes over the top when people sound like they are "doing a voice."

Master impersonator Kate McKinnon took the Delco accent to extremes during a Saturday Night Live segment: a trailer that parodies Mare of Easttown. It features McKinnon as “a grizzled lady detective…with a very specific accent.” While impersonations of Winslet's Delco speak haven't reached Fargo-like popularity, it's generated a respectable amount of buzz as Mare's "hoagiemouth" in Mare of Easttown has carved a small niche into the cultural zeitgeist.

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