Vandals on Venus — K.G. McAbee

Book Two of Series One.

When Nathanial Stone gets an emergency message from an old friend on Venus begging for his help, his duty is clear: he must go at once. His ward, Miss Annabelle Somerset, instead of agreeing to stay safely on Earth as he begs, insists on accompanying him to the dangerous tropical planet, home of huge reptiles.

Soon, Nathanial and Annabelle find themselves in the middle of a plot concerning a nefarious German officer, a brilliant English inventor, an Irish guide no better than he should be, a heavily-armed lizard-man and a clever American newspaperman. Can even they prevail against such odds?