Book 1 in the Frontier series
Striker once opened the gates between the Earth and the Centrum and was arrested by the Frontier guards. He had a choice: become a smuggler or join the Frontier guards at the Outpost. He chose to become a guard and now he must save the Earth. Somebody is trying to take destructive and poisonous weapons to Earth so that it withers like Centrum. The action-packed adventure culminates in a showdown in Moscow between Striker and a mysterious spy girl from the world called Hearth.