Amateur inventor Brett Conroy discovers aliens intent on invading Earth, but they contrive to make it look like Conroy himself is responsible for their dangerous explorations.; District Attorney Leary goes to great lengths to establish the innocence of an accused man, traveling to the Himalayas to verify his alibi.; An air patrol off the North African coast discovers a rampaging giant sea creature and try to warn everyone around of the danger.; tracing the history of the horse from prehistoric times to the present