After watching this episode, I had to wonder: why not more underwater crimes?
Like this classic locked-room mystery on Hawaii Five-0 Season 9 Episode 13.
I'm sure underwater photography jacks the production costs up big time. But with two ex-SEALs on FIve-0 and islands surrounded by all kinds of water, it is kind of a natural idea.
Seemingly, everyone on the team is comfortable in the water. Granted, maybe the imports, Danny and Grover, not as much. But still ...
Between the dead body with the bends and Reed Diamond guest starring as the backer of Neptune One, you just knew there was something hinky about the underwater lab.
This should have been a case right in Steve's wheelhouse.
He knew all the physiological dangers from his history of diving and had years of experience over the rest of the team.
So I was surprised when he sent Junior down in the sub with Tani and Adam.
I understand one skilled diver had to be held in reserve for just such a rescue as McGarrett ended up making.
But I figure Steve going and Junior staying behind would have been a better use of personnel.
But McGarrett has been doing more of that recently, giving his people opportunities to stretch.
Maybe he's feeling the mileage and is starting to make plans for succession. Who knows? It's good long-term thinking nevertheless.
For the most part, Junior leading the underwater team worked out.
He had the diving expertise and was aware of things, such as the impact of oxygen deprivation and the transmission buoy, the others on his squad were less likely to know about.
There was the one misstep when Tani had to save his disoriented ass but those things happen. He was lucky to live and learn.
Still, his sending up the buoy with detailed information gave Steve the sitrep he needed in order to make his death-defying rescue dive.
About that dive -- c'mon. Aging, irradiated, battered Steve went straight up with one breath to the surface with little ill effects while his younger cohorts headed for the hyperbaric chamber?
I don't pretend to understand the physiology of diving but seriously?
As for the murder itself, Jason had to have stumbled on something he shouldn't have witnessed.
So Neptune One couldn't have just been doing scientific research. Planning for illegal mining of a rare, valuable substance made so much more sense.
When selecting the culprit, I should have chosen the least-likely suspect, the team member who wasn't armed or incapacitated in some manner.
Yet she was flustered enough to contract the bends making her escape, after the cunning work she had done on the lab?
That didn't add up for me, but it was poetic justice.
I did think that, as they thought they were dying, Junior and Tani would speak the truth about their feelings for each other.
But nah, too soon I guess. Everyone knows where it's going, but the will they/won't they are destined to continue at least a little longer.
As for Adam, well, at least he got to tag along with the second team.
You know, for someone that used to be a high-ranking Yakuza official, this is one major step down. Free Ian Anthony Dale!
It was good that, after surviving, Junior went to mend fences with his father. In that masculine, pounding out your emotions with a hammer kind of way.
That situation has been lingering largely since Junior first appeared, so it's good to see some tentative progress.
I would have loved to have seen the hyperbaric chamber scene, with Adam and Junior arguing over anime versus cartoons, driving Tani crazy. Cartoons, by the way.
I thought we had seen the last of Grace after her brush with death on Hawaii Five-0 Season 9 Episode 12.
But we did get to see her being smothered by Danny early on, begging for a crime to rescue her.
And, now that circumstances have thrown them together, it seems like a Danny-and-Rachel reconciliation may be in the works.
Otherwise, why would McGarrett have been quizzing Danny so hard about it? That wouldn't be the worst thing for Danny.
None of the subsequent relationships have worked out either for him or for Steve.
To review Danny and Rachel's relationship, watch Hawaii Five-0 online.
How did Junior do in charge? Can Adam be saved? Anime or cartoon?
Dale McGarrigle is a staff writer for TV Fanatic. Follow him on Twitter.