Synthetic Men of Mars
Synthetic Men of Mars is a science-fantasy adventure by Edgar Rice Burroughs, the ninth book in his Barsoom series that began with A Princess of Mars. First published in 1940, it sends the hero John Carter and a young companion to the city of Morbus, where a council of mad scientists grows artificial men in vats - hormads - who soon multiply beyond control. Like the rest of the series it is pulp adventure: sword fights, captures and escapes, and a race across the Martian landscape. It reads as a late entry in a long-running saga rather than a good place for new readers to start.