Agents of SHIELD has always been able to get me talking about writing. It’s nice that I still get that, and actual good TV now.

On the most recent episode, we finally find out why May is called “the Cavalry,” why the story is so garbled among SHIELD agents, and especially why May absolutely hates that term. As with many things in the show’s run, this didn’t need to wait so long. Half of the episodes between the premiere and the mid-season finale in December could have been cut or truncated. However, that doesn’t mean that the writers didn’t pick an excellent time to tell the story. That’s an important factor to consider when dishing out backstory.

Spoilers ahead.

Backstory can often come in the form of infodumping. In “Melinda,” we didn’t get that. The two storylines weaved through each other in a delightful dance, with each one explaining the other. On the one hand, we have Skye meeting her mother and becoming more comfortable among the Inhumans; on the other, we have a story about May’s own doubts and demons. They could easily have been two separate stories, but they were connected very skillfully.

May’s backstory informed both of the current plots. It seemed to just start out talking about why she was starting to feel out of place. It begins by making us feel out of place — a laughing, smiling, joking May, easygoing yet clearly the same person. Suddenly, the story of “the Cavalry” takes on significant value, because we know that this is the moment that made her change. This is a moment of great tragedy.

And as we see (again, spoilers), it’s an American Sniper moment. The film, not the book. She’s forced to kill a child.

Think about how that could impact her. It’s not just that it was a kid. May was trying to be a mother. She and her husband mention it at the start of the episode, and she wants it all — field work and her own children.

By the end of the day, she’s lost both. She flinches at her husband’s touch, as it reminds her of the child she killed; and she gives up field work, requesting a transfer so she can lose herself in pushing papers.

It’s a powerful story about trust and the reason why she keeps a barrier between herself and the rest of the world. Why she values control so much. And here, in the present, she’s lost control. She’s not sure she can trust Coulson. She’s struggling to gain control before it all becomes too much again.

There’s a moment at the start of the episode when Morse is saying she doesn’t think May even knew about Coulson’s secret activities. May’s mouth twitched. I thought that was odd, because May is usually so impassive. By the end of the story, we know exactly why May was barely able to hold in her emotions. We know why she can’t let herself feel too human.

That, as I said, weaves into the other plot of the show. In the Inhuman city (which I will call Attilan until told otherwise), Skye finds out that Jiaying is her mother, and that this relationship has to be kept secret. It seems like a strange thing until the backstory reveals that May was actually dealing with a rogue Inhuman who had stolen Terrigen crystals to transform her daughter, whom Jiaying had decided wasn’t ready for the Mists. It was because the child had “a darkness in her,” but her mother, Belyakov, decided she knew better. The result was a disaster.

If the other Inhumans knew that Jiaying was Skye’s mother, she says, then they would assume that Jiaying had done the same. That she had shown favoritism for her daughter, who hadn’t gone through the normal training and preparation before encountering the Mists.

This is why I say the backstory came at an excellent time. It’s immediately relevant, to not just one but two plotlines. On top of that, it was shown as a story in and of itself, with a discernible three-act structure that is cut to underscore the absolute tragedy of what May experienced.

Here’s hoping that Agents of SHIELD continues like this.