Jan and London return home to find Evelyn and Amsterdam pacing outside, worried sick, and Abuja standing out of the way, looking nervous.

Jan - Hello, I think perhaps they were concerned.

Amsterdam notices them, and dashes at them.

London - Now maybe we should be concerned!

Amsterdam proceeds to tackle London, hitting him hard enough to send him onto his back.

Amsterdam - Where have you been?! You weren't at lunch, then you weren't at dinner, then you weren't in your room -

London - I took a walk and got lost...

Evelyn - I was worried sick when you didn't come home last night!

Jan - I'm very sorry, Evelyn. However, I think we made a very important scientific discovery in regard to genetics last night.

Amsterdam - What's that supposed to mean?!

Jan - Its some sort of an enigma. Come, we need equipment for this.

Jan bounds into the house, followed by London, then Evelyn and Amsterdam. Tokyo, this time tinkering with the cartridges for Pokémon Let's Go instead of playing them, watches the four of them all head into Jan's room. Warsaw also sees, as he was watching Tokyo work.

Tokyo - One of these days I'm going to become curious about what they're always doing in there.

Warsaw - Well, I'm curious now. You coming with me?

Tokyo - Well... No time like the present, I suppose.

Jan takes up a needle and quickly scores London on the nose, collecting a blood sample. She applies the collected blood onto a slide, and puts it under her microscope.

Jan - Wow...

London - What?

Jan - Your nose is really dirty and that wasn't a good sample.

Jan proceeds to rub alcohol on London's foreleg and quickly punctures it with a different needle. She takes this superior sample and puts it under the microscope instead.

Jan - Yes! Okay! As it turns out, it is very difficult to see DNA through this microscope.

London - So, what does that mean?

Jan - It means that we must perform field testing.

London - You mean, that has to happen again?

Jan - Yes, that would be the most likely course of action.

London - Ohhh, science...

Amsterdam - What are you talking about?

Jan - Something very odd happened to London last night, and I mean to get to the bottom of it.

Evelyn - What kind of very odd something?

Jan - I don't want to say for certain, because I can't explain it at all.

Meanwhile, Tokyo and Warsaw, who were eavesdropping at the door, stay long enough to hear the time of the field test (at dusk) and quickly get away before they are noticed.

Tokyo - Something very odd... Something to do with London's DNA.

Warsaw - Maybe his DNA glitched and he became a Flareon or something. Isn't Eevee DNA really long and complex?

Tokyo - Yeah, but I thought it stabilised after evolution... Whatever it is, we'll find out if we spy on the field test.

They resolve to wait until then. After coming out of Jan's room, London goes and eats a large breakfast, ravenous from having skipped three meals already.

At the end of the day, Jan, Evelyn, London, and Amsterdam go out into the forest. Warsaw and Tokyo discreetly go after them. Night falls, but clouds cover the sky, and Jan isn't glowing.

Evelyn - Why aren't you lighting up like usual, Jan?

Jan - Because the moon is obscured. I don't light up without moonlight.

A gentle wind is blowing, and clouds move from the moon. Jan begins to glow, and London begins to change. He doubles up and falls down. Amsterdam rushes to him.

Amsterdam - Ah! London! What is it?!

She jumps back as London seems to grow. Tokyo and Warsaw get closer to see better.

The fully transformed London sits up. Despite having eaten a huge dinner, he still finds himself hungry. He begins to sniff, and finds a tasty tomato smell.

Jan - Hello London?

London stops sniffing and regains his focus.

Amsterdam - You're still my little brother?!

London - Yes, I'm still me.

Evelyn - That was so cool!

London - I'm sorry, but I just need to investigate something real quick...

Jan - What's wrong?

London - I'm still hungry, and I can smell tomato and sugar. I need to see what it is.

London stalks off in Warsaw and Tokyo's direction, much to their chagrin and dismay.

Tokyo - What was he talking about, "tomato and sugar?"

Warsaw - I smell like ketchup, and you smell like candy, and now he thinks we're food! Let's get out of here!

London goes back to the others.

London - On closer inspection, it smelled more like Warsaw and Tokyo.

Amsterdam - How can you tell what they smelled like from over here?!

Jan - I have a theory... At the same time the moonlight hit me, he began to change, which could mean that his suppressed Umbreon DNA was rendered active momentarily to begin some sort of reaction. Then, he has a superior sense of smell, perhaps from Leafeon, which uses the enhanced scent capability to communicate with plants chemically.

London - But these changes are definitely not based on any segment of Eevee DNA. No Eeveelution has fangs or claws or fur like this, and they definitely aren't this big.

Jan - Yes, you see, that's the problem, I don't know where those are coming from... Let's try and...

London - Um, before we do anything else, could you excuse me for a second?

London bounds off into the forest.

Jan - Oi! I am not finished! Where are you going?!

Jan, Evelyn, and Amsterdam follow through the thick woods, but they can't keep up. Eventually, they find London, just swallowing something.

Jan - London! What was that?!

London - Oh, that? It was just some random Poochyena...

Jan - You just ate a Poochyena?!

London - Yeah?

Jan - You can't just do that!!

London - Well, the alternative is far less pleasant for you.

Jan - What? What's that supposed to mean?! Where are you going?!

London bounds off in search of more Poochyena, and this time the others cannot catch up. They stop to think.

Amsterdam - Okay, that seemed pretty uncharacteristic of him... I don't think he would act that way if he was just hungry.

Jan - Wonderful. So its London, but not thinking straight. That's frightening.

Evelyn - Maybe we should just wait here, and then he'll come back?

Jan - I don't like the idea of just sitting here, but I don't have a better plan yet...

They wait, and eventually London does come back, carrying another Poochyena in his mouth. He drops it in front of himself and holds the very frightened creature down with a paw.

London - I thought maybe I'd share!

Jan - Did you eat them alive?!

London - Yes? Is that wrong?

Jan shudders violently, then calms herself.

Jan - Okay, um... It'll be fine. Just let this one go.

London instead scoops up the animal and eats it.

Jan - London!! That's not at all what I said!!

London - I'm sorry! I've been really hungry this whole time! I've eaten, like, five more already and I'm still hungry!

Amsterdam - Five?!

Evelyn - I don't know a lot about biology, but that sounds pretty impossible to me...

Jan - Spit that one up.

London - But I just said that I was...

Jan - Do it for science!

London - Ohhhh...

London begins to retch, but nothing comes up. London begins to panic as he worries about making Jan angry.

London - I swear! There's nothing!

Jan - Hm... This is entirely inexplicable...

Jan suddenly takes out another needle and scratches London on the leg again, causing him to bellow in pain.

Jan - Incredible! His blood has turned yellow! What is this?!

Amsterdam - Watch out!

Jan - wut

London strikes out at Jan, slamming her against a tree. Regaining control of himself, he calms down.

London - Oh, my goodness! I didn't mean to do that!

Jan - There's no problem, I suppose it was to be expected...

London - I could've done with a warning.

Jan - You could've, but I wanted to see how you reacted to surprise. And it turns out, you react differently.

Amsterdam - So? I already told you what I think, remember?

Jan - Yes, I was just testing another theory.

London - What theory?

Jan - You are you, being London, but this evolved form is you and something else, I think. We should probably stop testing this.

London - So, how? It seems like its supposed to happen at night?

Jan - Rather, it seems to happen in the light of the moon. You usually aren't out in the moonlight, so if you stay indoors like normal, you'll be fine.

Amsterdam - That doesn't sound like a permanent solution...

Jan - Right now, I don't think there's another option available to us.

London - Well, if it only happens in moonlight, I should be okay... Although, I don't know how this started...

Jan - We can trace it when we get home.

Having talked the whole night, day breaks, and London is transformed into his normal self.

London - Whoa! I feel... I feel like I just woke up from a dream!

Jan - But you were fully conscious!

London - I know, and I remember, but it was like my brain just wouldn't think normally, like it was being guided...

Jan - This is very mysterious.

Evelyn - Can we go home now?

Jan - Yes, I suppose that'd be for the best.

They head for home.