Archons hiding in Saturn satellites

SG-1 searches for an ancient weapon which could help them defeat the Ori, and discover it may be in the Ori's own home galaxy. As the Ori prepare to send ships through to the Milky Way to attack Earth, SG-1 travels to the Ori galaxy aboard the Odyssey. The International Oversight committee have their own plans and SG-1 finds themselves in a distant galaxy fighting two powerful enemies.

a space alien struggles to ingratiate himself among humans without blowing his cover

Ganymede is the cup-bearer of the gods. Though he shows some superficial signs of age, the protection of Jupiter and his distance from the sun keep him in a state of eternal youth- his younger, liquid self cross-hatched with a cracked and ageing skin.