The threat of the Upside Down grows in Stranger Things season 3, episode 2, "The Mall Rats", and raises a lot of questions about the future. Stranger Things is an unusual show, a blend of classic horror and lighthearted teen drama. "The Mall Rats" places these themes side by side in an entertaining and effective way, and as a result tells a tale that's pretty unique.

On the one hand, the Mind Flayer's mysterious plans continue to progress; Billy is his agent, and Mrs. Wheeler almost becomes one of his victims. Nancy and Jonathan learn that something weird is going on with the town's rats, and Joyce discovers a strange electromagnetic field affecting Hawkins. But while these advance the main plot, Stranger Things season 3, episode 2 also finds a lot of time to explore the teen romance. Hopper's intervention causes Mike to ditch Eleven for a day, and Eleven spends time with Max instead. In a curious way, this episode is possibly the most character development Eleven has seen since she was introduced.

Related: Stranger Things: 5 Big Questions After Season 3, Episode 1

So let's explore the mysteries of the "The Mall Rats;" what is the Mind Flayer's plan, what are the Russians doing at Hawkins, and why has Joyce picked up on an electromagnetic field affecting the entire town?

5. What Exactly Happened To Billy?

Stranger Things season 3, episode 2 is amusingly reluctant to explain just what's happened to Billy. The episode opens with him escaping the abandoned steelworks and fleeing in his car. He then finds himself experiencing a traumatic vision of the Upside Down, in which he comes face to face with a dark reflection of himself leading a group of shadowy people. Soon he's taking others to the steelworks, presumably to undergo the same process. Given the visions, it's possible that Billy has been replaced by a doppelganger. Alternatively, Billy could simply be a new host, infected by the Mind Flayer virus.

4. What Is The Mind Flayer's Goal?

Heather's mouth bound with tape in Stranger Things.

Right now, the Mind Flayer's goal is a mystery. Stranger Things season 3, episode 2 suggests it desires human agents; one of Billy's visions shows him as the first of a small army of people under the Mind Flayer's control, and at the end of the episode he brings a new victim, Heather. This is a very different modus operandi to season 2, where the Mind Flayer simply intended to get through the Gate and conquer the Earth; this time around, it's being a little more strategic. It may be that it wants to reduce the chances of the Gate being closed on it again by taking control of the species who've opened it.

3. What's Affecting The Electromagnetism Around Hawkins?

Joyce has always been one of the smartest characters in the show, and in Stranger Things season 3, episode 2 she intuitively realizes that something is going on in Hawkins again. She learns someone is generating an unstable electromagnetic field across the town, a massive one that stretches from Joyce's house to downtown. This would be a massive and expensive project, presumably drawing on the local electricity grid, explaining the blackouts. The obvious implication is that Hawkins Lab may well be up and running again.

Related: Stranger Things: The Ultimate Guide To The Expanded Universe

2. What Are Russians Doing At Hawkins?

Of course, it may not be the American government who are responsible for reopening Hawkins Lab. Dustin has intercepted a coded Russian transmission, and in Stranger Things season 3, episode 2 he and his friends attempt to decode it. Ironically, it's Steve who realizes what may be the most important thing, though; he recognizes music in the background of the recording, and discovers that the transmission was from the Mall itself. It seems a Russian agent was sending coded messages while they were at the Mall, which is a frankly bizarre twist. What is it about Starcourt that's so important?

1. Will Eleven and Mike Get Back Together?

Hopper has done a good job of intimidating Mike, warning him to give Eleven some space, and as a result, he lies that something's up with his grandmother. This is the kind of deception Eleven cannot accept, and she dumps his ass. It feels like a temporary thing - Lucas states he and Max have broken up and gotten back together five times - but Mike is clearly going to have to make it up to Eleven.

Related: Stranger Things Season 3 Cast & New Character Guide

Other Questions After Stranger Things Season 3, Episode 2

Stranger-Things-Mayor-Kline

Meanwhile, Stranger Things season 3, episode 2 raises a whole host of other curious questions. What's going on with the rats and the fertilizer? Nancy and Jonathan discover that rats around Hawkins are dining out on some pretty strange substances, which has to be the Mind Flayer's influence. How is Mayor Kline connected to the Russians? At the least he's in their pocket. And just why does a tiny bear at the Mall cost $350?

More: What To Expect From Stranger Things Season 4