In this gripping action-adventure tale geared for younger audiences, long-time chums Mark and Jack are living as the house guests of the brilliant inventor Professor Amos Henderson, who enlists their help to build a first-of-its-kind vehicle that can be used for underground exploration.
In this gripping action-adventure tale geared for younger audiences, long-time chums Mark and Jack are living as the house guests of the brilliant inventor Professor Amos Henderson, who enlists their help to build a first-of-its-kind vehicle that can be used for underground exploration.