Ultima V continues the story of the Avatar begun in Ultima IV. The game begins with Lord British captured on a mission of exploration in a newly discovered Underworld. The Avatar (player) is called back through a portal to Britannia, where tyrant Lord Blackthorn rules with an iron fist and is backed by 3 mysterious "shadow lords".

With a deep plot and rich interactive world, Ultima V substantially raised the bar for RPGs of the day.