Siblings Hal and Harper Confront Adulthood as Dad Starts New Family

In the upcoming Sundance 2025 series Hal & Harper, actors Cooper Raiff and Lili Reinhart portray a pair of codependent siblings navigating the challenges of adulthood. The show, which premiered at Sundance earlier this year, follows Hal and Harper as they confront major life changes, including their father's announcement that he's having a baby with his girlfriend Kate, played by Betty Gilpin.

The news of their father's new family surprises both Hal and Harper, but it hits Hal particularly hard. He confesses to his sister that he's "really upset" about their childhood home being sold, even though he says he's "so okay" with his dad having a baby. As the siblings grapple with this shift in their family dynamic, they're also forced to reexamine their own close-knit bond and the ways it has both comforted and constrained them.

Throughout the eight-episode series, Hal and Harper's relationship is explored in depth, with the trailer hinting at the blurred lines between their closeness and codependence. As one character tells Harper during an emotional moment, "You are safe. All of the feelings are safe." The series promises to delve into how the siblings' childhood experiences have shaped their adult lives and relationships.