Lost Race of Mars

Are the Old Martians really a lost race — just withered mummies lying in dark caves? Or are they still alive — somewhere on the red planet?

Sally and Jim must find out. They must help their father discover if the Old Martians still exist. His life work as a scientist is at stake!

But it's not easy. They are only visitors to the Mars colony in the year 2017. And no one really wants them there.