A Classic space opera of the 1950s. 17 year old Bart Steele takes on a mission his father could not complete- trying to discover the source of the Lhari interstellar drive. The Lhari hold a monopoly on interstellar travel and humans who attempt to discover their secrets are hunted down and killed. ( )

An entertaining juvenile sci-fi tale featuring an enterprising and courageous young man on the trail of his father's secrets. ( )

I think this is first science fiction story I ever read. My brother had a copy and I read it in the late 60s. I still have that original paperback and read it again every few years. Well written and very imaginative. ( )

I didn't want it to end! If the there were a another book or a series of books I'd still be reading! ( )

This is not up to MZB's normal standard. Whatever you think of the plot, and I don't agree that it is all that predictable, the medical details are so bad that they disrupt the suspesion of disbelief this sort of book depends on. ( )