If someone says "below zero and C.J. Box" in the same breath, a vision of frigid Wyoming weather would immediately pop into mind. But that would be wrong. "Below Zero," the ninth book in the Joe Pickett series, involves the lowering of carbon footprints. Add a Chicago gangster, his rabid environmentalist son and a long-dead daughter to the mix and the action takes off.

In "Winterkill," the third Pickett novel, Box introduced April Keeley, a girl who Joe and wife, Marybeth, took into their home and family. During the fiery climax, April was killed with her biological mother in the camp of a survivalist group known as the Sovereign Citizens. Six years later, the Pickett family — including daughters Sheridan and Lucy — is still dealing with the trauma of that night.

Now it seems that someone is playing a horrible hoax on the family when Sheridan gets a message from a friend that says, "Tell Sherry April called." Then Sheridan starts getting text messages from "April." Joe is convinced that there is no way April survived, but soon details that only April could know make Joe consider the possibility that it really is April. Being the kind of man he is, Joe takes time off work and begins a quest to save the daughter he failed to protect before.

After the events in "Blood Trail," the previous book, Joe has been banished to the remote town of Baggs, Wyo., as a substitute game warden. The governor wants Joe safely out of the public eye before he uses his unique investigative abilities again. The major downside of this posting is that Joe is living far from home.

One of this series' strong points is that Box involves the whole family, his Joe is no lonely hero. Another signature theme of the Pickett series is Box's use of environmental issues that affect the "New" West.

In "Below Zero," Box uses the concept of carbon footprints, how much energy is used by individuals without regard for the environment or the future. To illustrate the concept, Box introduces David "Stenko" and his son, Robert, who is obsessed with getting his father's lifetime energy use offset so that it is not only neutral but below zero.

Robert, unfortunately, twists this beneficial concept by eliminating those who flaunt their energy use. This duo is on a collision course with Joe as they head west on their mission.

Meanwhile, Joe has enlisted both the FBI and his old friend Nate Romanowski in his search for April. Nate is a fugitive from the FBI and is taking a risk by coming out of hiding to help. When Joe discovers that the locations of April's texts coordinate with the places where unusual murders have taken place, he is afraid that the young girl is somehow involved. That would be the cruelest of events, to have April back but then lose her to the law.

Box has crafted a story that is as current as environmental terrorism and as old as a father's love for his child. He then sets the story in his beloved, well-described Wyoming and even takes Joe to the big city of Chicago by way of Devil's Tower. The action is brutal and unforgiving as the two pairs of father and child struggle toward their goals.

"Below Zero" is more of a thriller than a mystery, and the pace is relentless. The characters are fascinating, and their actions range from the heroic to despicable.

Box really knows how to create a complex situation, add suspense and then twist the tale with surprises that make for an intense and satisfying read. Box has become one of the West's most anticipated storytellers.

-- Leslie Doran