James Rollins pushes his newest Sigma Force installment toward more of an eco-thriller than the typical techno-adventure-special ops-thriller mashup that makes up much of the series. That's not to say there isn't an entity interested in weaponizing the newest find. There is. Such entities feel more like a distraction than the intellectual adventure exploration of the source material. 

In Tides of Fire, Rollins links Aboriginal mythology, Theia impact theories, the panspermia hypothesis (octopuses and other life from outer space), and a contrarian Out of Africa theory. He creates several fascinating thought exercises on top of a physical plotline, including massive quakes, deadly tsunamis, and volcanic eruptions. This shouldn't be a surprise. The stakes are always high. 

What's missing this time out, it seems to me, is a sense of anything potentially horrific. Sure, seeing the world burn would be horrible, but such a world-ending fate feels tame compared to some of the other events Sigma Force has dealt with over the years. They have had to deal with quantum-disrupting Nazi scientists, ancient nanotechnology, dark energy from outer space, and biodiversity extinction (to name a few). The consequences are real this time out, but the threat isn't necessarily as sinister as a few bad apples. 

Tides of Fire still ranks as one of the better Sigma Force outings because Rollins presents some science-fact that is even more interesting than some of his other forrays. Reading it might make us rethink some scientific truths we've come to cling to as fact. And that always makes for a fun read.