'Chicago Med': Vicki Glass Returns After Toxic Chemical Crisis

Chicago Med ended a particularly stressful episode with a surprising return, which will likely make Ethan Choi's life even more complicated.

After the doctor said goodbye to his sister Emily — who is headed to start a new life in Vegas with her baby daddy — he saw himself in a life-threatening situation after the disgruntled husband made a reckless decision in the hospital E.R.

As the man tells Ethan (Brian Tee) that he blames him for his wife's death at the hospital in the past, he reveals he has a mysterious toxic chemical with him, which could put lives at risk.

Maggie (Marlyne Barrett) and April (Yaya DaCosta) suspect something may be going and April approaches the room, but Ethan tells her that everything is okay to keep her safe.

After Ethan tells the man the details of his wife's tragic case, the man loses it and opens the jar with the chemical, as Choi tackles him to try to stop him. With the chemical out in the air, the hospital is forced to call a code orange, and evacuate, bringing the Chicago Fire crew and Chicago P.D.'s Haley Upton (Tracy Spiridakos) in to investigate.

After evacuating the room, Ethan returns to take the man outside, further exposing himself to the mysterious toxic chemical. Later, he refuses to slow down despite looking visibly affected by the toxin and he collapses.

April freaks out at seeing Ethan hurt, especially when she realizes he was trying to keep her safe earlier. Later, April and Sharon (S. Epatha Merkerson) disagree when there is only one dose of medicine that could help either the man or Ethan, and it goes to the person responsible for the crisis since he's in more serious condition.

When they find out that there's another dose that could help Ethan in the E.R., April puts herself at risk by running in and getting it without protection.

Once the crisis is done, and the fire department reveals that the man released cyanide into the hospital, the doctors are able to stabilize Ethan, as April realizes that she still has feelings for him.

When Ethan wakes up, however, he is surprised to see that Vicki Glass (Cynthia Adai-Robinson) — who hasn't been seen since season one — is sitting on his bedside. Apparently the doctor failed to update his emergency contact and the hospital called her after what happened.

Vicki announces that she is back in town after living in Germany for some time, and April walks by the room and sees her ex connecting with his former love interest.

Chicago Med fans will remember Vicki as a doctor at the VA Hospital who was Ethan's first love interest on the NBC medical drama and left to work in Germany. Her reappearance will probably mean more obstacles in the road to Ethan and April getting back together, though hopefully it doesn't take too long.

Chicago Med airs Wednesdays at 8 p.m. ET on NBC.