As in later Lucky Starr books, most of the action of David Starr, Space Ranger takes place on a single planet, in this case Mars. Most of this planet serves as an agricultural colony, exporting grain, fruit, and other commodities to the crowded Earth. The planet's three cities are domed, as are the central buildings of the outlying farms. Once outside the domes, humans must wear breathing masks.

The entire Martian colony depends on agriculture, and human survival on Earth depends on the produce of the isolated Martian farms. Thus, when David Starr opposes a corrupt landowner, the stakes are high. Asimov draws a sharp distinction between the Martian cities, which are much like any city on Earth, and the distant domed farms, which are virtually beyond the reach of law.

Asimov points out in his 1978 preface that the canals that he pictures on Mars are now known...