On the Defiant side you will have to walk into Abyssal Precipice to begin this quest.
On A New Era for the Abyssal you will have to fight Tideweaver Norla and then go into Iron Pine Peaks to meet with the Faceless Man at Illumination Point (Whtiefall). He will then set you on the quest Meetings of Interests. Head to Steampike Pit, which is North East in IPP to use the spyglass and learn of the meeting. You will need to locate the large pile of books to get the Disciple of the Deep. Afterwards return again to the Faceless Man in Illumination Point.
He will now send you to Meridian to find out what is going on with the scholars at Orphiel’s Tower. Go to the 2nd floor where you will find 2 crazed librarians and a book. Grab the book. Head up to the 3rd floor and you will see Alyete Bathsube. Talk to the librarian and then head to see Eddie. You’ll find him on Shoreward Island which is North of Freemarch and east of Silverwood. You’ll have to swim over there so be prepared to get into your fatigued bar. He’ll give you a quest item that you will need to use to bind the book. To do this go back to Orphiel’s Tower, 2nd floor. When done return to the Faceless Man.
Now you will get the quest A Personal Request. You will need to find and escort the Faceless Man’s mother safely in IPP. Speak to him again and he’ll give you the quest Rescue Mission and will then port you to Minera. Once she is safe you will then need to head back to Meridian to the Orphiel’s Spire.
To finish the quest Blood in the water you must kill 100 Abyssal Cult Members. You can find them in water rifts in Shimmersands, Iron Pine Peaks or Stillmore. An easier way to kill them is to go outside of AP and slaughter them there or in very west IPP right before you get into Stilmore. The Abyssal Cult Members there all have the names that start with Nightblood. When finished go to Uriel Chuluun in the office of the unseen in Meridian. Turning this in will give you the option of four lessers… Demented Dance, Frozen Bulwark, Maddening Storm, and Tidal Frenzy.
You will now have the quest Explorers of the Deep which will ask you to go to Rurik who is in the bottom level in Chancel of Labors in Ipp. Finishing this quest will give you the achievement Exploring the Deep. Now on to part 2!!