The Hollywood stars met while filming the second season of "Fargo," which aired in the second half of 2015.
A year and a half after the pair finished filming their roles as a married couple, they struck up a romance.
"I knew that she would be in my life for a long time," Plemons, 32, told the New York Times.
After having already spent decades in show biz, the two would often spend many late nights running lines with one another.
Kirsten Dunst (left) and Jesse Plemons in ‘Fargo.’ They met while filming the show before their romance blossomed. (Chris Large/FX/AP)
"We laugh about the fact that we were two child actors and we both made it out OK," Dunst, 38, said.
The pair became engaged in early 2017, and they now share a 2-year-old son, Ennis.
Plemons has earned himself two Emmy nominations — one for "Fargo" and another for "Black Mirror" — he also played a major part in "Breaking Bad" and has starred in a handful of critically acclaimed films since then, all crafting a career and a skill praised by Dunst.
"He works so hard at what he does," said the actress, an Emmy and Golden Globe nominee herself. "He takes everything very seriously and embeds himself very deeply."
During the ongoing coronavirus quarantine, Plemons said he's been forced "to look at what’s in front of" himself.
"I've spent years of constantly learning the same lesson over and over again, that you can work and work and work on something, and bang your head against the wall and know it inside and out — but then, in that moment, if you’re not relaxed in your mind and body, that’s all for nothing,” explained the "Game Night" actor. “A lot of that work won’t be seen unless you’re grounded and present. I just don’t think there’s ever anything wrong with attempting to be present.”
Jesse Plemons (left) and Kirsten Dunst have been engaged since 2017 and share a 2-year-old son, Ennis. (Photo by Axelle/Bauer-Griffin/FilmMagic)
According to People magazine, Plemons offered up some praise for his fiancee last year when she was awarded a star on the Hollywood Walk of Fame.
"Aside from the brilliant actor you are, I’ve also had the even greater pleasure of getting to know you as a person outside of work,” gushed the star.
He added: “Seeing the kind of mother, wife, daughter, sister, friend and cohort you are is why I and all of your friends and everyone else are here today and why we all love you. It’s for the incredibly generous and amazing person that you are.”