Why Fans of 'Chicago Med' Are Devastated by Dr. Halstead's Exit (SPOILERS)

Spoiler alert: This article contains major spoilers for the Season 8 finale of Chicago Med.

After eight intense seasons, Dr. Will Halstead (Nick Gehlfuss) is hanging up his white coat at Gaffney Chicago Medical Center. He's been saving lives on Chicago Med since day one, but sadly, he's had enough.

The attending physician has always been the heart of the show, and fans will miss him dearly — but how did we get here? Why did Halstead leave Chicago Med? Keep reading to find out.

In the Season 8 finale, titled "Does One Door Close and Another One Open?" Halstead has had enough of the corrupt new owner of the hospital, Jack Dayton (Sasha Roiz), and his million-dollar investment in the O.R. 2.0. He and the rest of the doctors agree O.R. 2.0 should be shut down, but since Dayton is at the top, he gets the final say.

As expected, Dayton doesn't care that the O.R. 2.0 technically killed someone — but Halstead won't give up without a fight. He becomes dead set on stopping Dayton's plan, stating, "I can't stand what this place has become."

In the end, Halstead and Dr. Song (T.V. Carpio) join forces and successfully sabotage Dayton's publicized surgery. The two tampered with his procedure to depict a false incision, loudly displaying the system's known flaw. Halstead later stops by Goodwin's (S. Epatha Merkerson) office and admits he was responsible for the system glitching.

He tells Goodwin that he acted alone — but she knows Dr. Song played a part — and claims he couldn't stand by and watch O.R. 2.0 kill another patient. Halstead then hands Goodwin an envelope, and we all know what that means.

"My letter of resignation," Halstead explains. "If Dayton comes looking for a culprit, you have one."

Goodwin says though she doesn't want to, she has "no choice but to accept [Halstead's] resignation." He understands what he's doing, but at this point, there's no turning back. She warns him it's going to be difficult, reminding him that she can't "give [him] a reference, and Jack Dayton has been known to be vindictive."

Halstead then gathers his things from his locker and leaves the hospital — for good. In the final moments, he arrives at the Seattle airport and reunites with Natalie (Torrey DeVitto) and her son. Although we're sad to see Halstead go, we couldn't be happier that he and Natalie are together again.

Speaking of Halstead and Natalie's reunion, Nick Gehlfuss told Deadline it "makes so much sense."

"I think that the relationship has come full circle, but of course, it wasn't the only reason Will decided to leave Med. I think Will had been seeking elements of Natalie in every relationship; I don't think [he] ever really got over her," Nick told the outlet. "It was really so great to see Torrey, too. She called me to let me know she was coming."

He added, "We fell right back into our work rhythm as if we hadn't had any time off. It was a beautiful moment at the end of the episode that I hope brings some closure to the fans." Well, based on the social media response, we think fans are over the moon to see that #Manstead is endgame.