- 1 Biography
- 2 Personality
- 3 Season One
- 4 Season Two
- 5 Season Three
- 6 Season Four
- 7 Season Five
- 8 Season Six
- 9 Quotes
- 10 Trivia
- 11 Appearances
- 12 Gallery
Ethan is the son of Navy veteran Patrick Choi. He has a younger sister called Emily. Ethan followed in his father's footsteps and joined the Navy as a medic. During his time in the military, he worked in a medical aid camp in Baghdad, as well as serving on the USS Carl Vinson.
Upon returning to Chicago he became a resident in Emergency Medicine at Gaffney. He is still a Navy reservist and occasionally attends recruiting events. During season 5 he is called back for a six week deployment. Throughout the show he is shown struggling with PTSD.
During season 1 and season 2 he dates VA doctor Vicky Glass. Right before she arranges for him to meet her parents, he breaks up with her due to his feelings for April Sexton. Ethan and April date and eventually move in together and become engaged, but their relationship comes under strain several times. When Ethan's sister Emily comes back into his life, April feels that he is too hard on her. Ethan and April become frustrated when they are unable to conceive, and their first IVF treatment fails. When April reveals she illicitly kissed Crockett Marcel, he comes to physical blows with him.
Ethan is one of the more emotionally restrained doctors, which is attributed to his military background. He does, however, have moments where his emotions surface, such as after the death of Jason Wheeler, where he cries upon seeing Wheeler's body in the morgue. After a mass-shooting gives him flashbacks of war, he cries into April's shoulder. Ethan believes in strictly following protocol, which often puts him at odds with other doctors such as Will Halstead and Crockett Marcel, who often take a more gut feeling or risk-reward approach to the treatment of their patients.
Ethan assists in treating an influx of victims of an elevated train derailment.
Ethan decides to force deliver a placenta stating that he had done it before, as OB service was busy. However, the procedure isn't well done and the 14 year old girl is left with almost having to go through a hysterectomy. He felt guilty about what happened, specially considering he judged the girl for abandoning the baby. He later tries to help the girl and she runs away from the Hospital. The morality of the situation arises discussions between him, Dr. Manning and Dr. Rhodes.
Will treats Gertrude Kovack, a patient that seems rather racist because of her comments toward April's ethnicity. She later spots Ethan outside her room and tells Will she would prefer him because "Orientals make the best doctors" relating it to stereotypical math skills. Ethan plays along and quotes Confucius. Will later mentions that Ethan is Korean.
Ethan and April kiss for the first time.
Ethan and April are officially a couple, but she wants to keep their romance on the down-low, especially since another nurse is already complaining about favoritism on Ethan's part.
Ethan is poisoned after being trapped with a family member of one of his previous patients. The poison eventually spreads through the whole hospital but shown visibly affecting him, to the point of making him bedridden
Ethan and April get a pregnancy test, which turns out to be negative. They treat a young boy with loss of vision due to a brain abnormality brought on by hypothyroidism. Watching the parents' love for their child, they discuss some day having a child of their own.
Ethan gives the new batch of third-year medical students their introductory speech, noting that medical student Steve is especially excited about emergency medicine. Ethan and Crockett run out to an ambulance that has skidded off the road a few blocks from the hospital. He, April and Steve treat the paramedic extracted from the crashed ambulance. When the power goes out they move the patient into the hybrid OR. April offers to stay behind and help Steve, but Ethan calls her away with him.
Upon returning to the hybrid OR, they discover that the patient has developed abdominal compartment syndrome, which Ethan relieves by cutting open his abdomen. The visual nearly causes Steve to go into shock, but Ethan helps him snap out of it. As a new generator arrives, the patient goes into V-fib, but they are able to revive him.
As he and April are leaving for the night, they run into Steve in the lobby. He announces that he is not coming back due to the stress of his first day in the ED, and the prospect of having to do this work for the rest of his life. Ethan wonders whether he was too focused on his patients' needs and not enough on Steve's needs, but April replies that it is normal to forget to take care of each other in stressful situations. Ethan counters that it is not normal, and that April is able to do so all the time, complimenting her mindfulness and awareness and saying she will make the "best mom ever." They express their love for each other and kiss.
Ethan meets a patient who reveals that he has terminal brain cancer and has been drinking a cocktail of medicine that will arrest his heart within the next few hours. The patient wants Ethan to declare him dead so that his brain can be cryonically frozen in the hopes of finding a cure in the future. Ethan tries to persuade Dr. Charles to declare the patient decisionally impaired, but he refuses. When the patient arrests, Dr. Charles relents in order to give the parents a little more time with their son. Daniel eventually convinces the parents to let their son go, as that is what he wanted, to Ethan's disapproval.
Ethan and the rest of the ED staff deal with the influx of patients infected with the flesh-eating bacteria.
Ethan is annoyed when Crockett and Noah try to poach one of his patients. They disagree over the course of treatment, with the fact that they are unable to obtain the patient's previous medical records adding further complication. When the patient opts for surgery and pulls through, Noah is surprised Ethan isn't more happy, to which Ethan apologizes.
Ethan and April treat patients affected by COVID-19. He and April clash with Dr. Lanik over whether to allocate the last ECMO machine to a patient who is dying of COVID-19.
Ethan is promoted to Head of the Emergency Department after Dr. Lanik steps down, much to Will's disappointment. He immediately starts to micromanage Will, second-guessing him on the treatment of a patient with pneumocephalus. April congratulates him on his promotion, and promises to let him know when he is being a hard-ass. Shortly thereafter, they argue over allowing the mother of a patient dying of COVID-19 to visit her daughter. When Ethan comes around to allowing the mother to visit, she is instead brought in in critical condition, having contracted the virus as well.
Under pressure from Goodwin to improve the ED's finances, Ethan moves April from the COVID-19 ward back to the ED. Ethan, April and Dr. Charles treat a patient named Lisa who is afraid of needles, and they become suspicious when she becomes increasingly anxious to leave, can't present a consistent story, and appears unfamiliar with modern technology. They eventually figure out that Lisa is actually a woman named Kelly Bissett who disappeared as a child.
- (to Sarah Reese): "We rise or fall together."
- He has blood type O-negative.
- He works as a volunteer at the zoo.
- He mainly treated patients with gunshot wounds while in Baghdad.
- He got a parrot in season 2 to help with his PTSD.
- He is one of the few other characters in the One Chicago franchise that has a military background. Others include Dean Archer, Jeff Clarke, Jay Halstead, Greg Gerwitz, Justin Voight, and Alvin Olinsky.
|You Can't Always Trust What You See||To Lean In, or To Let Go||Be the Change You Want to See||Status Quo, aka the Mess We're In||Change Is a Tough Pill to Swallow|
|When You're a Hammer, Everything's a Nail||A Square Peg in a Round Hole||Just as a Snake Sheds Its Skin||Secret Santa Has a Gift For You||No Good Deed Goes Unpunished... in Chicago|
|The Things We Thought We Left Behind||What You Don't Know Can't Hurt You||Reality Leaves a Lot to the Imagination|