The Diviner, sometimes called the Obelisk, is an item brought to Earth by an alien race known as the Kree and used in their experiments on Inhumans. When a Diviner is taken by an inhuman into the temple in the Kree City it releases the terrigen mist thereby causing Inhumans present to experience terrigenesis.
The Diviner's metal is deadly to humans and causes any person who touches it to have their bodies slowly turned to stone. Cal told Whitehall that this is way of protecting itself from those it doesn't "divine to be worthy."
If an inhuman touches the Diviner, the Diviner begins to glow and the symbols on it light up.
Dr. Whitehall was convinced that the Diviner was a weapon with the potential to kill millions of people and it was his hope to use it like the Red Skull used the Tesseract to conquer the world.
After the inhumans rebelled against their creators, the Kree left several Diviners behind on Earth. Over time, the inhumans developed their own culture and began to view terrigenesis as a rite of passage.
In Jiaying's era, the inhumans currently had five Diviners in their possession, but Jiaying feared that if anything should happen to the Diviners then her people would lose their ability to transform forever; thus, Jiaying had one of the Diviners melted down and from it the inhumans learned to grow their own terrigen crystals thereby making Diviners obsolete to them.
In Chaves, Portugal, 1945, Hydra unearthed a Diviner and Dr. Whitehall immediately began experimenting with it. In his experiments, Whitehall would force people to touch the Diviner then measure how long it'd take them to die.
After the death of Red Skull, Agent Carter and the Howling Commandos raided a Hydra base where they arrested Dr. Whitehall and seized the Diviner in the name of the S.S.R. The Diviner became the first 0-8-4. When the S.S.R. became the modern day S.H.I.E.L.D., the Diviner was moved to a storage facility and was marked with a level 10 security clearance.
When S.H.I.E.L.D. was destroyed by Hydra, the U.S. government took possession of the Diviner along with hundreds of others artifacts, most of which the government had no idea what to do with.
In "Shadows", Coulson's team tries to steal the Diviner from a government warehouse before Carl Creel, an agent of Hydra, can. As soon as Izzy touches the Diviner, however, her hand and forearm slowly begin turning to stone. Creel eventually kills both Izzy and Idaho and walks away with the Diviner.
In "Heavy is the Head", Creel uses his absorbing powers to stop the the Diviner's power from killing him. However, before he can deliver the Diviner to Hydra, Raina steals it from him. When Raina touched the Diviner it doesn't kill her, however, and instead glows and shows marking in the same style as Garrett and Coulson's carvings.
After picking up the Diviner and activating it, Raina informed "the Doctor" that the Obelisk worked. The "Doctor" corrected her and noted that it let her live. He promised to tell Raina more about the Diviner if she would bring his daughter to him.
In "Face My Enemy", Raina is approached by Dr. Whitehall who tells her she has 48 hours to bring him the Diviner or she dies; also, Whitehall warned Raina that there is no place she can hide where he wouldn't find her.
In "A Hen in the Wolf House", in an attempt to reverse engineer the effects' of the Diviner, Hydra creates a deadly toxin using tissue samples they took from a victim of the Diviner. Hydra poisoned a wedding party with this toxin killing eight people with it, six of which were U.S. Navy sailors that were part of an anti-Hydra unit. However, Dr. Whitehall was disappointed that the toxin didn't kill everyone at the party and realizes they still need the Diviner.
Later in the episode, Raina begs Cal to let her have the Diviner so she can fulfill Dr. Whitehall's demand, but Cal refuses to give it to her until she brings him Skye. However, after Cal sees Coulson hugging Skye, he delivers the Diviner to Dr. Whitehall himself. Furthermore, he promises to teach Whitehall how to survive the Diviner if he helps him kill Coulson.
In "What They Become", it's revealed that Skye can also touch the Diviner without dying, in a similar way Raina can. After Raina takes the Diviner to the temple in the alien city, the Diviner retracts - opening to reveal a crystal and releases the Terrigen Mist. Trip tries to stop the Mist by destroying the Diviner, but it's too late as all three have already started to become encased in stone. Skye and Raina survive, both unleashing their Inhuman potential. But Trip was impaled with fragments of the Diviner casing and, not being an Inhuman himself, died.
In "Who You Really Are", S.H.I.E.L.D. learns the true origins of the Diviner and learns there's more than one on Earth. The case that was supposed to contain them originally held at least six.
- Dr. Whitehall mentioned that the Red Skull believed the Diviner may hold the answer "to death itself."