While working on an invisibility formula, British scientist Peter Brady suffers a tragic accident that makes him invisible. Unfortunately, there is no antidote, so while working on a method to regain his visibility, he undertakes missions for his government stopping bad guys.

The first of its genre, this sci-fi thriller is suspenseful, action-packed, television drama at its classic best. Brady is originally forced to be a state secret, and he is locked up. However, he eventually convinces the UK government to let him return to his laboratory to search for an antidote. Despite this, British Intelligence soon recruits him for assignment. He becomes a celebrity as a result of using his special feature to help people, solve crimes and defeat spies.