This Is Us,” season 4, episode 5 titled “Storybook Love,” introduced yet another mystery in the episode’s closing moments, reports TV Insider.

We learned, in the show’s past timeline, that teenage Kate has a boyfriend named Mark, her colleague from work. He joins her for a family dinner and the two seem to be having a good time together.

It wasn’t until the episode’s final moments, and present-day Kate’s reaction to the polaroid photo of her and her boyfriend at the time, that we learned that there is something up with him.

Speaking to Kate, in the final scene, Rebecca recalls the year after Jack died.

She was trying hard to hold everyone together and wanted to believe her kids were happy. So much so that she “didn’t see what was happening.”

It’s a rather cryptic line but, before she could elaborate, Kate interrupted her saying, “I didn’t see what was happening either,” and leaving fans wondering what happened between her and Mark.

The show’s executive producer Isaac Aptaker fueled the mystery.

“Fans should have a healthy amount of concern,” Aptaker revealed in his EW interview.

Describing the way Rebecca and Kate are talking about the relationship, he said that there’s definitely something looming there.

In the end, he confirms fans’ suspicions by saying that Mark might seem like a good guy, now, but it definitely looks like the relationship didn’t end well for Kate.

As reported by TV Insider, there are quite a few theories out there about what really went wrong between Kate and Mark.

Let’s dive right in.


It’s not a secret to anyone that Kate’s life has been an emotional rollercoaster since the show’s beginning. And losing her father is, without a doubt, her biggest trauma.

In the previous episode, it seemed that she was finally ready to get out into the world again.

Then she meets Mark and he gets her a job at the record store.

In this episode, we learn that the two are dating already. Everything seems to be going well. However, Mark could have been the one who broke Kate’s heart.

Although Mark seems nice, there are definitely signs that point towards there having been an abusive relationship.

Take their first meeting, for example. Minutes into meeting this boy, Kate is already sharing too much about herself, revealing that she is at her most vulnerable point. She tells him about her burned-down house and her father’s subsequent death.

Is it possible that by sharing this deeply personal stuff, Kate had made herself an easy target for manipulation? After all, she suffers a drastic physical change and Mark might as well be the catalyst for this. We’ll have to wait and see.

Other signs

In this episode, there’s a situation that seems to indicate that Mark might not be as nice as he seems.

He surprises Kate by showing up at her new house and basically invites himself to an awkward family dinner.

It may seem kind of cute until you realize that he practically stalked Kate by looking up for her address. Even Kate said that was sweet, but also creepy.

There’s also an issue of Kevin and Randall who don’t seem to like Mark even though he seems charming.

While Randal is subtle about it, Kevin is straight-up hating on Kate’s new boyfriend. He says he’s a few years older than her, but is it possible there is more to that comment than meets the eye?

After all, Kevin and Kate are twins and he may be sensing that his sister is in danger and that there is something deeply wrong with this guy.

Only time will tell. Tune in Tuesdays 9/8c to find out how the mystery unfolds.