Riven: The Sequel to Myst

"Enter a deceptively beautiful world torn apart by age-old conflicts... where secrets lie hidden at every turn... and nothing is as it seems. You must search. You must explore. You must summon every spark of intellect and intuition. Only then will you learn the truth about this troubled land and its inhabitants. You must let Riven become your world -- before an entire world is lost."

Riven starts right where Myst left off, in the basement of K'veer in D'ni where Atrus was imprisoned at the end of Myst. Once again, the player plays the role of the Stranger, Atrus's friend. Atrus needs the Stranger's help. His wife Catherine is trapped on the age of Riven, an age written by his mad father Gehn. Gehn has proclaimed himself God of Riven, and rules over its inhabitants.

Edited from original source: Wikipedia