The pair, who play a married couple on the popular FX show, were first linked back in May when they were spotted kissing while hanging out together in Los Angeles, then again in September while at an Emmys after-party for their show. The former child star and her Friday Night Lights beau have been seen together many times in Los Angeles since.
Dunst previously dated her On the Road co-star Garrett Hedlund, whom she split with in April after four years together.
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Reps for both Dunst and Plemons have yet to respond to the news.Read more at Instyle