Episode 109
In the fourth of four semi-final rounds, three more of the contestants use the $50,000 prize money to develop their inventions. In this episode Doug Hall mentors and judges the three semi-finalists.
Other episodes for this season
In the fourth of four semi-final rounds, three more of the contestants use the $50,000 prize money to develop their inventions. In this episode Doug Hall mentors and judges the three semi-finalists.