Worried about Ben and Maddie’s health, Ryn turns to her own kind for help. Helen continues to worry away at the mystery of exactly how her parents died. Xander and Calvin have to deal with the reappearance of a familiar face.

After Maddie’s little outburst at the Pownall dinner table crowned a run of peculiar behaviour on her behalf, Ben and Ryn are more worried than ever about the effects of the siren song. Ryn, who remains charmingly direct and simple in her approach to problems, announces she’s going to fix it, and goes off to fetch a healer from among her own kind.

But it’s more complicated than that, and so the trio find themselves asking another favour of Nicole and the Navy to find something that may not only help their own situation but also provide some interesting additional information to the military in their ongoing study of the merpeople. It’s certainly one of the more FX heavy episodes, and although we don’t get to see an awful lot, what we do see is impressively rendered.

Meanwhile, Helen can’t stop wondering about what exactly happened to her parents, and a dig through the newspaper archives at the local library gives her an idea that they may in fact have been killed rather than dying in a tragic accident. Where they died is almost as important as how, and as she digs deeper, she ends up with a lot of suspicions aimed at various people. Pleasingly, the show is smart enough to keep all those people mysterious in terms of what exactly it is that they know and where they stand. It’s clear that this is going to be one of the big plot threads that carries over into another season if we get one.

And Xander and Calvin (who now seems to have hit the inevitable bad run of luck in his gambling) are confronted with the re-appearance of a familiar, though not entirely welcome face. What’s worse is that they don’t really know what to do with them, and the people they could ask aren’t contactable.

As to Nicole – Natalee Linez continues to do sterling work keeping the audience on edge as to exactly where her character’s loyalties lie. I’m pulling so hard for her to be genuinely on side with Ben, Maddie and Ryn, as well as for her attempts to rekindle things with Xander to be true. But every so often that little bit of doubt gets thrown in there. She’s an excellent antagonist and the writers are making best use of her – here’s hoping she’s also a permanent fixture if season three happens.

Verdict: Like a shark, Siren never stands still, always advancing its narrative and branching its plots while retaining perfect focus and never feeling cluttered or scattered. 9/10

Greg D. Smith