The Time Traders

Andre Norton writes some great adventure science fiction and this is one of her best that I've come across. This one has it all, time travel, cave men, aliens and being as it was written in the late 50's, evil Russian agents.

Ross Murdock is a kid of the streets. He's been busted so many times he has burnt all of his bridges. Or so he thought. As he faces the judge for his latest mis-adventure, waiting for the hammer to fall, he is surprised to hear an offer given to him. If he volunteers for this mysterious project he won't face jail time. Ross Jumps at the chance, with the thought that somewhere down the road he will make good on his escape.

However he is not permitted any opportunity. He is rushed away, put on an atom jet and flown so fast that he loses consciousness only to awaken in some unknown area. He later learns through another "volunteer" that it is somewhere in the arctic. This other "volunteer", Kurt, wants to escape as badly as Ross does. And later that night Kurt and Ross make good on their escape from the facility and steal an enclosed atomic snow mobile type of machine. It is after they had made some distance away from the compound that Ross discovers that his "pal" Kurt, is much more than he seems. He is a double agent for Russia. They have a battle inside the enclosed machine and Ross lucks out when Kurt hits his head and is knocked out. After changing seats and tying Kurt up, Ross heads back to the compound to turn himself in and dispose of Kurt. It was the fact that he was on his way back with the captive Kurt that saved Ross from being a captive himself, because they couldn't allow him to go back into society after being shown some of the things at the base.

Thus begins this tale of time travel and espionage and discovery that is well paced and full of adventure. Andre Norton wrote SF adventure that is as good as anything Heinlein did. If SF adventure is your cup of tea, I recommend Andre Norton. Highly!