Thanks to last week’s Thanksgiving holiday, we had to wait two weeks to find out what happened to Jack after the previous episode’s cliffhanger ending, when he collapsed in the bunker after a bloody coughing spell. This week provided us an update on his health, as well as a reunited Team Free Will, a frightening Nick, and the ever-charming Rowena, who returns to help the “wee Nephilim.”

We also see the possible return of not one, but two, archangels, who we thought were long gone and far away.

Let’s talk about the emotional and heart-wrenching “Unhuman Nature.”

Spoilers ahead, so beware!

The first scene opens on Nick, who seems to be confessing his sins or fears to an unseen therapist or priest. He says that he knows his recent actions are wrong, but he enjoys the feelings they bring him. Sounding more like Lucifer than the docile Nick we saw in this season’s first episode, we learn that he was trying to convince a priest to tell him the confessions of the only witness to his family’s murders – his neighbor Arty – in the hopes of learning more about that night. But as the camera pans out, we see the priest hanging from the wall, crucified. Nick has killed him.

In the bunker, Cas is attempting to heal or learn more about Jack’s failing health. He provides Sam and Dean with an update and tells them that he cannot figure out what is wrong with Jack. While the guys are talking in the hallway, they hear Jack collapse in his room and rush to find him on the floor, suffering from what appears to be a seizure.

They rush Jack to the hospital and demand to see a doctor. In the Emergency Room, the nurse at the desk demands the guys provide information about Jack. But the simplest of questions about Jack’s history prove very dfficult to answer. They muddle their way through the protocol, but Jack then collapses and is rushed to a room. Team Free Will waits outside the room for what seems like hours, pacing worriedly, hoping they can get some answers for their 2.0.

At a cafe, Nick meets a woman who we learn is the reporter that spoke with Nick the morning after his family was murdered. He asks her for any information she can provide about that night. He specifically asks her which beat cop was assigned to his neighborhood that night. Because she was the local crime reporter for the area at the time, she is able to produce a name: Frank Kellogg, who now lives in Montauk.

Back at the hospital, Jack’s doctor finally emerges and tells the guys that she cannot determine what exactly is wrong with him. She does say that he is in total systemic failure and that his body is in the process of shutting down. After hearing this news, Sam and Dean decide that the hospital cannot provide the help that Jack needs. Knowing they cannot share with the doctors that Jack is a Nephilim, they decide to take Jack back to the bunker and call on Rowena to help.

When she arrives to the bunker with the Book Of The Damned in hand, frantic with worry, we learn that Sam told her that Dean was the one who was sick, so she would agree to come. However, once she arrives, he tells her that it is Jack who is suffering, and that he also happens to be the son of Lucifer. Upon hearing this news, Rowena packs up and begins to leave the bunker. She tells Sam that hearing that Jack is dying is good news because, knowing what she knows of the father, the world would be better off without the son.

Jack has entered the room at this point, and he overhears her say this about Lucifer. He tells Rowena that he understands her hatred toward his father and that he is trying very hard not to be like him. He also thanks her for saving the lives of so many people from Apocalypse World and tells her that Sam and Dean speak highly of her. His earnest words and boyish charm win her over, and Rowena begrudgingly realizes that she wants to help him however she can.

After trying several spells to improve Jack’s health, Rowena resigns herself to tell Sam, Dean, and Cas that she cannot heal him after all. She explains that a Nephilim, by its very nature, is very delicate and is held together by its grace. Without grace, Jack’s body is in constant chaos. “His cells are gobbling each other up,” she says. Cas immediately offers to give his grace to Jack, but Rowena says that only an archangel’s grace can help him. And without that, Jack will die.

At this point, something very strange happens to Dean. While Rowena is talking, Dean’s vision becomes blurry, and his hearing fades in and out. He eventually snaps out of it…but what just happened?

In town, Nick is parked in an alleyway at night, outside of a dance club. He is creepily watching a young woman talk on her phone and trying to convince himself not to get out of the car and presumably harm her. Eventually, he loses the battle within himself and walks up to her. After some innocent banter, the woman invites Nick to go into the club with her and meet her friends. Nick extracts a knife from his back pocket and considers harming her. But he chooses not to hurt her and screams at her to get away from him immediately. She runs inside the club unharmed.

At the bunker, Dean brings food to Jack and sees Jack packing a bag. He asks him what he is doing, and Jack says that he is planning on doing some traveling. He tells Dean that has realized he is not guaranteed an everlasting life, and he does not want to waste the limited time he has without seeing the world. Even mundane experiences like getting a parking ticket and getting bored appeal to him. Dean starts to say something, but Jack interrupts him, assuming that Dean will disagree with his decision. Dean corrects him and says that he does not, in fact, disagree with Jack’s plans.

In the main room, Sam, Cas, and Rowena are all researching ways to help Jack with his poor health. Cas informs Dean that nothing in their vast collection of Enochian texts shares any knowledge about Nephilim. Rowena shares that, after consulting with the greatest minds in witchcraft, the consensus is that nothing will help Jack. Sam, however, has discovered a Shaman, with the help of Ketch. The Shaman was a consultant for the British Men of Letters, Sam explains, and he is an expert in mysticism and can “solve the unsolvable.”

Once again, Dean suffers from another bout of wobbly vision and muffled hearing. No one else notices. Both times Dean has suffered from these spells, the conversation that was taking place centered around treating Jack — first, when Rowena explains what elements Jack needs to heal, and now, when Sam declares that he might have found a way to help him. Is Michael still residing in Dean, trying to listen in on Dean’s surroundings? And if he is, why is he concerned about how to handle a Nephilim’s health?

By the time Dean recovers, Cas announces that he will volunteer to meet with Sergei the Shaman. Jack enters the room, and he and Dean tell the others that they are leaving the bunker for the day to take “Baby for some exercise.” Sam and Cas both seem concerned about this, considering Jack’s failing health, but the pair leave anyway.

Dean and Jack pick up some burgers, and Dean passes the car keys to Jack, which seems to frighten him. Jack sits in the driver’s seat, and Dean starts instructing him, telling him that “‘R’ is not for ‘race.'” After some neck-wrenching starts and stops, that probably everyone who has learned to drive can relate to, Jack seems to get the hang of it. It becomes obvious that Jack is trying to do more than learn to drive… he wants to emulate Dean. “It’s like I’m you!!” Jack exclaims. He even mimics Dean’s posture and rests his arm on the door, driving with one hand like a seasoned pro.

Dean’s affection for Jack is very evident in this scene, and watching him reveal it was simultaneously uplifting and heartbreaking.

Back at the bunker, Cas leaves to meet Sergei. But before he does, he and Sam discuss the weight of Dean’s concern for Jack. Sam shares that Dean was very unkind to Jack when they first met and has never been able to forgive himself of that. Sam says that Dean has lost loved ones, like everyone has, but this is different. “Losing a…a son feels different,” Cas offers.  Sam knows that Cas is right.

Dean and Jack have now made their way to a local river to fish. Jack wanted to fish with Dean, because Dean once mentioned fishing with his father and how much he enjoyed that. Jack explains that he has come to the realization that life is not about traveling the world and seeing exotic places, but rather it is about spending time with loved ones. Jack seems at peace with the fact that his life may end very soon and tells Dean that he has had a good life.

Cas arrives at Sergei’s location. After surrounding Cas with a precautionary ring of holy fire outside of his home, Sergei invites him inside and makes him tea. Sergei explains to Cas his history of “knowing the unknowable” and “answering the unanswerable.” Cas asks him if he believes that Jack can be saved, if his condition can be reversed. Sergei says he believes that Jack can be “shocked” out of his condition, like “rebooting a computer.” Sergei presents Cas with a vile of archangel grace from Gabriel. Gabriel exchanged his grace, Sergei explains, for a spell that allowed him to hide away in Monte Carlo so many years ago. “With porn stars, yes I know the story,” Cas hilariously exclaims. After also receiving the required spell that must accompany the archangel grace, Cas races back to the bunker.

Nick has arrived at Frank Kellogg’s place in Montauk. Nick explains who he is and that he is there to talk to him about his family’s murders. Frank refuses, but Nick bursts through the front door, ties Frank to a chair, and begins his interrogation. After roughing him up with a series of harsh punches, Nick demands that Frank tell him what happened the night his family was murdered. He explains that his neighbor that night – Arty – reported seeing someone leave Nick’s house late that night, and that person was a cop. Arty felt pressured to change his story, because the police force wanted to protect their colleague. But we see through flashbacks that Nick forced the truth from Arty through threats of harm, and the story of the cop was true. We also see that Nick murdered Arty.

Frank eventually admits that Sarah, Nick’s wife, called the police that night because she thought she heard a prowler. Frank was on assignment that night and answered her call, alone. As he was walking up to Nick’s house, Frank claims that a man named Abraxys appeared. (This name gives Nick pause – he has heard that name before but cannot recall from where.) Frank continues to recount what happened and says that the next thing he remembers was being back in his patrol car, covered with blood. “My wife’s blood,” Nick says. Frank confirms this.

Nick surmises that this Abraxys creature must have possessed Frank and murdered his family without Frank’s consent or awareness. And even though Frank was not in control of his actions that night, Nick chooses to murder him anyway, in a horrifying display of brute force.

We now see that Nick is much more Lucifer than he ever was Nick.

At the bunker, Sam, Dean, Cas, and Rowena surround a seated Jack, ready to administer Sergei’s hopeful cure. Rowena recites the spell, and Jack absorbs his uncle’s grace. At first, it seems that the cure has worked. Jack’s eyes shine brightly, he hops up excitedly and exclaims that he feels a definite improvement. But he soon collapses and suffers another seizure.

Cas calls Sergei immediately. He explains to him what happened with Jack, and Sergei seems dismissive, saying that he is just a Shaman, that “science is sometimes trial-and-error.” Cas warns him that, if Jack is irreparably harmed, he will find him.

Back at Frank Kellogg’s house, Nick stands over Frank’s body and has obviously consumed several bottles of liquor. He drops to his knees and begins to pray. He says out loud that he claimed his rage would ease when he discovered the truth about his family’s murders. But he admits that he has been lying about that. He has been harming others because he enjoys it. “I like doing these things, and I don’t want to stop,” Nick truthfully says.

We begin to see another location, where everything is devoid of light. As Nick continues to pray and admit his truth, the black begins to form into a shape – the shape of a body.

I’m bonded to you and what you are. It’s how you first found me. I don’t know who I am, if I’m not you. No consequences, no pain, no sorrow. I want that back! I want it back.

I don’t want to feel now what I didn’t feel then. Where are you? Where are you?! Help me!

The shape displays red eyes upon hearing Nick’s prayers. We realize that he has been praying to Lucifer, and Lucifer is (quite possibly) returning from The Empty.

In the final scene, Team Free Will and Rowena watch over an ailing Jack. Dean feels guilty for taking Jack on a road trip, thinking it ultimately harmed him. But Sam and Cas assure him that the trip did more good than harm to Jack, because it made him happy.

Rowena walks up to the men, clearly upset, and tells them in no uncertain terms that Jack is dying.

What did you think of this week’s episode? Is Michael still residing in Dean? Was that Lucifer we saw forming from the blackness during Nick’s prayers? Leave your comments below, and stay tuned for next week’s episode, “Byzantium,” which will air on The CW on Thursday, December 6, at 8/7c.