I was rewatching H2O season 1 when I realized something: when 당신 think about, each original character has had their own season that sort of resolved around them. Let's start with the beginning:
Season 1: Emma
당신 may 또는 may not have noticed but the one who always gets seen 의해 Zane is Emma. She is the one who saved Zane, she is the mermaid that Zane saw twice (during his saving and with her red hair) and in the finale she told dr. Denman to go 집 while Cleo and Rikki just walked away.
Season 2: Cleo
This is not rocket science. The main villain of this season existed 의해 the cause of the 사랑 삼각형 between Cleo, Lewis and Charlotte. Cleo was also the one who first discovered her advanced power and the first to control it. She is the first one to get attacked 의해 Charlotte. In fact, she is the one who drives 샬럿, 샬 롯 insane to the point where she wants to take the trio's power; just for revenge!
Season 3: Rikki
This is just pointing out the obvious but Rikki is the one that season 3 is about. She is the only mermaid who has a obvious connection to the Moon Pool and the strange happenings. She is also the first one to get taken 의해 the water tentacle. She is the first one to gain the water tentacle's trust.

So tell me: what is your opinion about this? Do 당신 think it's just a coincidence? Sound off in a 코멘트 또는 코멘트 below.