The Commander is heroic and kind, as per expected of one of the world's greatest Supers. He is also caring and loving, especially when it comes down to family members.
The Commander was born to an unnamed father who also had powers and was a superhero. His childhood is a mystery.
The Commander attended Sky High at the same time as Jetstream (who he fell in love with) and Sue Tenny (who he viewed as strange). Using his super strength he was assigned to Hero Class.
After graduation, he was paired with All American Boy who became his sidekick. Eventually, they were captured by a supervillain named Royal Pain and her sidekick Stitches, but Jetstream rescued them and together they destroyed Royal Pain's secret weapon, the Pacifier. Unbeknownst to the trio, Royal Pain survived the explosion and she was actually Sue wearing armor. The Commander also believed, due to her electronic voice, that Royal Pain was male.
It is unknown if they were already married, but this marked the first time the Commander and Jetstream teamed up against evil forces. They worked by day as real estate agents, something Jetstream was already into when they defeated Royal Pain. They settled into a house and secretly built the Secret Sanctum underground, where they stored the Pacifier.
They would continue to do battle with forces of darkness, such as a large creature with a tentacle as large as the Commander's body, or common criminals, whom he and Jetstream are known to fight five at a time. They also bested King Kamurah, whose wooden surf board (which presumably was by no means ordinary, considering Stitches recognized it at once) was stored in the Sanctum. Either before or after besting him, and around half a decade after defeating Royal Pain, they had an affair, resulting in the birth of their son, Will Stronghold. The Commander and Jetstream became renowned for their triumphs, even being widely considered the world's greatest superheroes.
Role in the film
The Commander is first seen taking down a monstrous robot with Jetstream. After Will's first day of school at Sky High, The Commander entrusts Will with the key to the family's Secret Sanctum (after Will promises that he will never bring anyone else there); the place where all the family's trophies of past victories are kept, including the Pacifier, of whose origins the Commander explained to his son.
Later on, Gwen Grayson meets the Strongholds and invites them to be the recipients of the very first Hero of the Year Award, which will be presented at the Sky High Homecoming Dance. The Commander and Jetstream accept and go to Sky High when the event happens. During Gwen's presentation of the award, it is revealed that she is Royal Pain and she unveils the Pacifier, now with Stitches by her side. The Commander, Jetstream and many others attempt to stop her, but she turns them back into infants. After Royal Pain is defeated, the Commander is depacified along with everyone else.