While Resident Alien season 4, episode 4 starts in the past with D’Arcy and Ben almost getting together, we spend the rest of the episode in the present day. It looks like a wedding is about to happen!
Caution: This post contains SPOILERS for Resident Alien season 4, episode 4.
At the end of Resident Alien season 4, episode 3, Heather returned with a surprise for Harry. They’ve had children, and Harry would have been happy about this if he was still an alien. However, now that he’s human, he finds Heather’s alien form repulsive.
Is there any hope for them? Well, maybe, if Heather is happy being in her human form all the time.

Heather proposes to Harry in Resident Alien season 4, episode 4
Harry wants to try to pretend that everything is okay, and he doesn’t want to tell Heather that he’s human now because of what that will mean for them. Can they be together as human and alien? In the end, he decides to tell her the truth, and it’s clear that Heather doesn’t mind that. She proposes to him anyway.
There’s one caveat to their relationship. Heather will need to stay in human form, and as much as she’s disappointed in that, she understands and she agrees to it. However, she points out that her parents are racist against humans, and sure enough, that becomes an issue. Heather’s dad shows up and immediately attacks Harry.
The two end the episode realizing that they can’t be together. As much as they love each other and they have children together, Harry realizes that he can’t ask for Heather to cut herself off from her family. Because that’s what will happy if she goes through with the wedding. Heather left because of Joseph and the threat to her family, so it’s clear that family means everything to her. So, they head in their separate directions.
There’s so much growth in Harry in this episode. I love seeing him realizing that he has to sacrifice his own happiness for the happiness of someone else.

Kate thinks D’Arcy is just like her in Resident Alien
At the end of the previous episode, Kate remembered that D’Arcy was on the ship. Rather than assume that D’Arcy did something with her baby, she thinks that D’Arcy may have been like her. Maybe she got pregnant at some point, and now she doesn’t remember it.
Ben is terrible at trying to get information, but some of that comes from his past relationship with D’Arcy. They should be able to just come out and ask about this, although I don’t think they realize that D’Arcy knows that aliens exist right now.
What it all tells D’Arcy is that Kate remembers. It’s only a matter of time before she figures out that D’Arcy took the baby and is hiding the baby somewhere. D’Arcy can’t have Kate remembering to protect the baby, so the best option is to lie to Ben, even though it clearly hurts her. It looks like this will lead to D’Arcy and Judy becoming friends, as D’Arcy calls her afterward for a drink.
Oh, and who knew that Judy was so great at diffing graves! I just love that she didn’t ask what D’Arcy and Asta needed a grave for, and it’s not like anyone is going to take anything Judy says seriously anyway.

Mike tells Lena about aliens
Harry isn’t the only one revealing secrets. Mike needs to as well in Resident Alien season 4, episode 4. He tells Lena that she needs to stop the investigation in the woods because it’s not a human serial killer out there. Aliens exist.
Of course, she doesn’t believe him, because why would she? She’s not seen it. Mike tries to storm off, but he realizes that Lena was the one to drive, so they have an angry car ride home. Don’t worry; they make up, though. Mike even says that he loves Lena, which shows us how far Mike has come over the last four seasons.
As for Liv, she’s jealous at people seeing aliens, so she decides to put cameras up in the woods where Mike saw the Mantid. I feel for her, though, because we know that the Mantid is gone now. Heather ate him. But will she catch something else on those cameras? They’re sure to come up at some point.
The very end brings up something extremely concerning for Kate. As she buys some Girl's Guide cookies, one of the girls hands her a tracker. They're the Greys, making it clear that they are always watching her.
Resident Alien airs Fridays at 10/9c on Syfy and USA Network.