And now, speaking in a new interview, it's been revealed that viewers can expect to see more from John and Summer's unconventional "love story" when the show returns to screens in fall for its fifth season.
WATCH: Are you looking forward to Yellowstone season five?
Chatting to Entertainment Weekly at the Screen Actors Guild Awards pre-show last weekend, Piper confirmed that she will be making a comeback in the new season and also spoke about what fans can expect from the burgeoning romance between the unlikely couple - despite the fact that Summer is now behind bars.
"The love story is kicking into gear on Yellowstone," she said. "I know a lot of people watch it for the cowboys and the ranch, but I watch it for the love story."
She then teased: "We're turning up the heat. It's been a hard couple of years, let's turn up the heat for a minute."
Summer was arrested at the end of season four
As fans will recall, the relationship between the Dutton patriarch and the animal rights activist got off to a rocky start when they met at a protest outside Kayce Dutton's (Luke Grimes) livestock office. John had Summer thrown into jail when things turned violent but made it up to her by later bailing her out, which led them to strike up a friendship that soon turned romantic.
Are you looking forward to the new season?
John's daughter Beth (Kelly Reilly) made it obvious that she was not Summer's biggest fan from the start, first pulling a kitchen knife on her when she discovered that Summer had spent a night at the ranch and then getting Summer arrested again. As a result, the last time viewers saw Summer, she was facing up to 15 years in jail for multiple charges.
Meanwhile, John ended last season campaigning to take over as Governor from Lynelle Perry (Wendy Moniz), and it looks like he might have a fighting chance after he received positive endorsements from many in the community.
If John does become Governor, could his new sway with government figures help reduce or completely write off Summer's jail time? And if that happens, will his new status mean that he will have to keep his relationship with the convicted criminal on the down low?
Viewers will have to see how Yellowstone creator and writer Taylor Sheridan plans to square things when the show makes its return to screens later this year.
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