Force Five was not a single television show, but a syndicated series that showcased five different anime programs once a week, dubbed into English for an American audience. Danguard Ace was an Americanized version of Wakusei Robo Danguard Ace and only some episodes were included in the American release.
Danguard Ace ("Planetary Robot") centered around Earth's discovery of a new planet called Promete. Earth had become ravaged and almost uninhabitable due to overpopulation and a lack of natural resources, so a ship was sent to the remote outreaches of the solar system to explore the unspoiled Promete, which shared similarities with Earth's environment.
Unfortunately, the evil scientist Komisar Krell also discovered Promete, and he planned to move his own people onto the planet. After Krell attacked the first Earth ship journeying to Promete, the Earthlings built Danguard Ace to protect them from future assaults.
Danguard Ace had some parallels to the sci-fi classic Star Wars, focusing on a conflict between the good son and bad father. The hero of the story, Lieutenant Winstar, was the son of a great pilot whom he believed was dead. But in fact, Winstar's father was a prisoner of the evil Krell, who controlled the pilot's mind through a mask. Like Darth Vader, Winstar's father hid his true identity, taking instead the pseudonym Captain Mask.