Ultima V - Warriors of Destiny
Screen shot from PC version of Ultima V
No great improvements were made in Ultima V. There was a slight  improvement of graphics in general and a vast improvement of the dungeon  graphics. An artificial intelligence engine for the citizens of Britannia  was introduced. Now the people go on about their business instead of just  roaming around aimlessly like they had in Ultima IV. The combat system  had been improved so you could attack any square not too far away from  you with a long-range weapon. In Ultima IV, you could only attack N, S,  E or W.
Lord British has been abducted. Three of the remnants of the Gem of Immortality  which Mondain once possesed have materialized into three evil beings, known  as the Shadowlords. Lord British encountered these Shadowlords during an  expedition in a great subterranean system of caverns known as the underworld.  He never returned to the surface, and the people of Britannia knew not  if he still was alive. The Shadowlords then possessed the one called Blackthorn,  who was ruling in Lord British place. Blackthorn lost his mind and became  a cold-hearted tyrant who turned Lord British' virtues into a system of  laws that held the population with an iron fist. Someone in Britannia managed  to use a magic coin to summon the champion of the Quest of the Avatar,  who quickly collected his old companions to set out to find Lord British,  dead or alive.
Ultima 6