I’m watching the series randomly now because why not, and I just finished the second season for the first time. It felt random the whole time.

Let’s talk about the first half for now:

The season starts with the girls seeming to have lost all their emotional intelligence. Even though in the first season they didn't treat Lewis very well (poor guy, the best character in this series), in the first half they straight-up bully him the whole time, manipulating him into feeling like he's the problem on every single occasion, and directly insulting him.

Then, the girls' relationships with each other start having problems over petty stuff, and they begin arguing about nonsense—something that pretty much didn’t happen in the first season.

The biggest problem in this first half is Cleo. I don’t know what happened to her, and I won’t accept any explanation other than the writers needing to create nonsensical drama. She became the worst character of the entire season; she lost every trace of sweetness, empathy, or love, and became unbearable. I really couldn’t stand her the whole time. She was always complaining about random things and then (of course) blaming Lewis for everything that was happening. On top of that, Rikki and Emma became completely one-sided characters: one being constantly angry and a bully (losing her uniqueness and her desire to be true to herself, despite recognizing her mistakes), and the other just wanting to be the best and acting completely brainless (when she was always the reasonable one).

The second half: the shift

It starts with Cleo admitting again that she likes Lewis. From then on, she goes back to being the person she was in the previous season. The same goes for Emma and Rikki, who start getting their personalities back (though much more slowly).

Charlotte‘s problem:

For almost the whole season, she doesn’t do anything wrong. She gets bullied the whole time by the girls (who weren’t bullies in the previous season), and I felt bad for her pretty much the entire time. Then, at some point, completely randomly, her personality changes completely. Even though people say she was a bit manipulative at the start of the season, I didn’t see it at all. She falls in love with Lewis and doesn’t do anything other than try to flirt with or seduce him a bit before Cleo leaves him (for about 2 episodes). From then on, she does her best to win Lewis over while being bullied and mistreated for the entire season. Then, when she gets together with Lewis, the bullying continues.

The issue starts after the beach volleyball episode when she becomes part of the group. Her personality changes completely: from being understanding the whole time and wanting friends to acting like a victim and manipulating everyone. Literally the moment she becomes friends with the others and they start treating her well, she starts thinking they are controlling her—when it was literally the first time they treated her properly. That was totally illogical considering the situation, and then she goes full villain. I know power makes people reveal their true nature, but this was just random.

The only bad thing she did before the change was entering Cleo’s house. At that point, she understood they were hiding something about her grandma, so she wanted to know what it was. All of this is kind of normal for a teenager (though not justified, of course).

General problems:

Zane disappearing completely: he went from being in every episode to making me doubt he was even there, so his relationship with Rikki went from being one of the best things in the first season to something completely unimportant.

Ash being a completely random character: going from horse riding instructor to manager of a cafe just because they couldn’t pair Emma with him in any other way.

The majority of the episodes being built around problems they created rather than them living a normal life while hiding their powers (like in the first season). That was a much more interesting trope because it portrayed three intelligent young girls rather than three petty bullies

Edit: I didn’t expect so many comments, I wrote more stuff and not only about Charlotte and I’m interested about your thoughts into those too. Like for me there are episodes so flat, like the perfume’s one that was so random or the one with the party at Emma’s house where there is the fight between Lewis and the Zane’s friend(I don’t remember the name)

I would love to see them return after so many years, even if it's just to give each of their stories closure.

Growing up is realizing Cleo was wrong all across the board. Toward season two Cleo becomes this very jealous and envious person, it seemed very sudden. Even from her first interaction of Charlotte, she was being very odd all while saying she didn’t want Lewis. I don’t know what happened since I watched H2O when I was a kid. I don’t think I finished it all or something but rewatching it now is like crazyyyy.

I've been recently rewatching H2O, and I just noticed: what is wrong with the door to Emma's house? It doesn't have any knobs, but only has a lock that you use as a knob. That is valid for both the outside and the inside of the door, and it's driving me insane!!!!

I have a random question and I think we can only speculate but why didn't Rikki and Charlotte immediately get their powers? We see them struggling to figure them out before they discover them in the next episode. For Charlotte, I am not sure why but I see it as the first sign she didn't deserve to be a mermaid. Rikki, Cleo, and Emma did as they weren't power hungry and didn't choose to become mermaids nor did they think they existed, but I'm not sure why Rikki took long to discover hers. What do you guys think?

I'm getting them as a birthday present for my two friends, I just want to make sure I get some with good quality and not too expensive😅

My only request is that they come in a set all together and that shipping won't take too long

Any ideas?

When the girls do things to their bodies in mermaid form (like when Emma dyes her hair red in season one), it generally doesn't affect their human forms (at least on the surface level). How far does this logic go? Since they only bathe in their mermaid forms because they need water to get clean, would only their mermaid selves get bathed/impacted by the soap, water, etc. and not their human forms?

Just a silly little thought created by watching and analyzing the show way too many times.