In Curse Of Strahd, Strahd met with the adventurer Atlas Atruvian and told him the story of Zann and Berez; later, Atlas would witness this event through the Tome of Strahd. His ghost met with Pack when they adventured near their family home, pointing perpetually to Marina's monument in their cemetery. They produced a Blinsky Toys reproduction of Ireena Kolyana, Marina's reincarnation, to see if it would help Zann pass on. However, this only tormented him further, and he disappeared.
Zann Ulrich was the Burgomaster of Berez in central Barovia, and the adoptive father of Marina Ulrich. He was known to be a greedy and selfish miser that left his village and manor fall into shabby conditions, in the interest of hoarding wealth to himself. He sold a number of his family's old Spellbooks and valuables to Strahd von Zarovich, who at the time went under the alias Vasili von Holtz.
Though Zann cared for Marina, he was extremely harsh with her. Strahd, as Vasili, successfully began to woo Marina, who had discovered that she was a reincarnation of his beloved Tatyana Federovna. Made aware of this, Zann staked Marina through the heart before she could fully transform into Strahd's thrall. He then confronted Strahd, and overcome by disgust and horror, attempted to do the same to the Vampire lord. Instead, however, Strahd murdered the man, and in rage, summoned a great swell from the Luna River that resulted in the Flooding Of Berez.
Strahd did not initially kill Zann, but instead spent years torturing him before turning him into a Vampire Spawn. Over a century later, his physical form was killed, but his spirit remained trapped in Barovia. Unable to move on from the traumatic circumstances of his passing, Zann became a Ghost, haunting his destroyed mansion and obsessed with the grave he had buried Marina in.