'Grey's Anatomy': Alex Makes a Costly Decision About His Future After Jo's Big Bombshell

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Warning: Spoiler alert! Do not proceed if you haven't watched Thursday's Grey's Anatomy fall finale.

Alex Karev's life is crumbling before his very eyes.

On Thursday's fall finale of Grey's Anatomy, the suspended Grey-Sloan Memorial pediatric surgeon made a costly decision about his future that would dramatically stall his personal and professional lives.

With a trial beginning the next day for his assault case over beating up his fellow doctor, Andrew DeLuca, Alex made the decision -- to Meredith's many objections -- to take a plea deal. The result of such a decision meant Alex would be going to prison for two years, though it's unclear if he actually will go through with it. Darn cliffhangers!

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What prompted Alex to admit his guilt and plan to spend the next two years behind bars? Much of it was motivated by ex Jo Wilson's confession, the day before she was set to testify, that she was (and still is) married -- a secret she made DeLuca keep under wraps weeks earlier.

"I'm married to a guy who almost beat me to death. I can't divorce him because I ran away from him," Jo admitted in the Grey-Sloan elevator, afraid of what was to come. "Jo Wilson isn't my real name. That's why I couldn't marry you. That's how this whole thing started."

Ironically, Jo kept all of this from Alex out of fear that he would try to find the man and do something "stupid" that would get him "killed" or "in trouble" or "in jail." Because her testimony would be on the record, meaning her husband could locate her, Jo felt the need to tell Alex beforehand.

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Fearful of the ramifications of her testimony, Jo also hinted that she may be leaving Seattle and for Alex not to take it personally. (At episode’s end, Jo was seen leaving the hospital with a travel bag, as if she was possibly leaving town.) "This is your life. You're Jo Wilson. You belong here," Alex said, trying to calm her, before hatching his own plan.

After settling on what he would do, Alex told Meredith of his decision to take the two-year plea deal. Understandably, Meredith wasn't having it, trying to dissuade him from destroying his life.

"You think this is noble what you're doing? It isn't. It's giving up. It's buying into everything you've ever said about yourself and I won't let you do it," Meredith pleaded. "You will be destroyed. Your life, your career, everything will be finished. Who you are will be gone."

In a last-ditch effort to persuade Alex from agreeing to the deal, Meredith left one last voicemail on his phone as he sat in the lobby of the District Attorney's office. "There were five of us and now it's just you and I. It can't be just me. It can't be," she said.

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Will Alex go through with his decision? We'll have to wait until Thursday, Jan. 19, when Grey's returns! While we wait for its return, several other key Grey’s characters also found their lives upended. Here are where some of your favorites ended up at the end of the episode:

Owen and Amelia. Things had been rocky between the two in recent weeks, leading Amelia to leave a “Dear Owen” letter telling her husband not to search for her, as she bolted out of town. And in a surprising turn of events, Owen revealed to Nathan that he had cheated on his first wife, Cristina.

Arizona and Eliza. After getting called out by Grey-Sloan’s new consultant Eliza for not picking up on her flirting, Arizona finally agreed to have a drink with her. Certainly bodes well for the two!

Richard and Grey-Sloan. Though Richard lost his post overseeing the interns at the hospital, it seems a mutiny of sorts may be in progress. After finding out the hard way that Eliza was his replacement, Richard learned that not everyone is happy with Eliza’s hovering presence.

Ben and Miranda. Not an entirely significant update for the married couple, but the two decided that their mantra of keeping church and state separate simply isn’t working. What will that mean moving forward? We shall see!

Earlier on Thursday, ET spoke with Grey's star Jason Georgeabout Alex's dicey situation.

"He’s looking at serious, serious problems that aren’t normal doctor problems. He’s in court with a serious ‘We’re not going to see you for a while’ problem," George told ET.

“One of the things I loved about Grey’s is they’re not afraid to let their characters be jerks,” he added. “They don’t always have to be shiny, happy, likable people -- especially Karev, who is the poster boy for that.”

For more on this season of Grey's, watch below.

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