As your character or party is exploring the Northern Greilyn Jungle during the primary quest, Morain will be seen having encountered the Hak'u, who kidnapped her niece Tanzi. She demands to be told where Tanzi's been taken or says she'll kill him. But the Hak'u attacks, injuring her, uttering over his shoulder that he'll kill her first as he absconds across the nearby bridge, blowing it up after crossing it. Head up the hill and speak to her and she'll mention that she's already taken her sister Hesla back to Eirulan and speak worriedly of her neice Tanzi, who was taken to a cave nearby. Agree to find and rescue her missing neice Tanzi to initiate this quest, whereupon Morain will return to Eirulan.

Morain has been injured and then returns to the Eirulan Infirmary. Continue on toward the Elven Shrine and as they go up the hill, leaving the Northern Greilyn Jungle and enter the Western Greilyn Jungle, have your character or party take the immediate path to the west, to trigger a cut scene where you'll see a Hak'u head down the path a short distance and open a spiked wooden gate and then walk on through and disappear into the cave entrance. Continue on this path and under the spiked wooden gate to encounter the entrance to The Hak'u Caves right behind it.

Enter and you'll note the star on the compass mini map, which is their destination. Unfortunately they can't head straight for it as a fence separates them from Tanzi. So make a U-turn to the east, then go down through the gap in the fence to the south. Loot the three barels to the east for some gold and the chest straight ahead as well. Note the switch on the right gate post, which can be used to provide easy access to the second ghost in the Spirits of Aranna quest, who stands just on the other side of the bridge to the west.

Continue northwest through the campsite and a cut scene will unfold, where you'll see Tanzi imprisoned in a cage, guarded by a Hak'u Signaller. Hrawn, who's another Hak'u and son of the deposed high priest, arrives and kills her guard and frees Tanzi, telling her to take off and warn his father. Hrawn is berated by the usurper high priest for doing this. Hrawn then takes off to find his father. Tanzi then says did you see that, implying that not all Hak'u are bad, and then returns to Eirulan, which your group should do as well at some point.

Once the Fourth Morden tower has been destroyed and your character has lost her prisoner collar back in Eirulan, head south from the Eirulan teleporter to the tramway for the Great Hall, Infirmary. Get on the tram and take it across to the next tram, then take it across to the Great Hall. Head north towards the Infirmary, where you can see a star on the Compass mini-map, which indicates their intended destination. Enter the Infirmary and you can see Hesla lying on a cot with an orange question mark icon above her head. Go speak to her to receive your reward, which completes this quest.

Hesla then strongly suggests striking at the Hak'u, but Tanzi tells of being freed by Hrawn and that he's hiding in a cave in the Southern Greilyn Jungle. Her mother tells Tanzi to go get some rest and doesn't believe her. She tells you to go there and get to the bottom of this. Agree to do so to initiate the second part of this quest.