Note: This story contains spoilers ahead from “Severance” Season 2, Episode 7.

From the very first moments of “Severance,” Mark’s (Adam Scott) missing wife Gemma (Dichen Lachman) has haunted the Apple TV+ original series. But it wasn’t until after Season 1 that the show discovered how devastating Gemma’s loss truly was.

“That was something I felt very grateful to Ben [Stiller] and Dan [Erickson] about. They really let us have a say in shaping some of that backstory,” Jen Tullock, who plays Mark’s sister Devon, told TheWrap.

Before filming on Season 2 started, Tullock had a lunch with Erickson where she pitched the idea that the four of them — Mark, Gemma, Devon and her husband Ricken (Michael Chernus) — used to be an incredibly tight-knit group. It’s a dynamic that makes sense considering Mark and Devon’s relationship. Though Mark is often shown as being annoyed by his brother-in-law, they came up...