An idealistic young doctor begins his first day under the supervision of a tough, brilliant senior resident who pulls the curtain back on all of the good and evil in modern day medicine. Lives may be saved or lost, but expectations will always be shattered.
A blackout at Chastain Memorial Hospital requires the staff to treat their patients without the help of any technology. Bell orders the staff to stop accepting new patients and transfer those on life support, but when a child in need is rushed to the ER, Conrad and Devon go against the mandate. Meanwhile, Mina and Austin are tasked with performing heart surgery on a premature baby, despite the lack of power, and Nic works tirelessly to organize the staff and patients who stay during the blackout.
Bell grows frustrated when Marshall Winthrop, Conrad's dad and new chairman of the board, requests Conrad's input in his discussions about the hospital's expenses. As Conrad and Nic work to cut costs for their patients in need, Julian Lynn, a sharp and sophisticated medical device rep, meets the staff at Chastain and inserts herself into the ongoing work of the doctors to promote her costly products. Meanwhile, Mina's relationship with Micah struggles in the wake of his healing process, and Devon is tasked with showing the eager new interns around the hospital.
Nic and Conrad contemplate their past when they team up to diagnose a happy husband and wife who are both admitted to the hospital with mysterious symptoms. Bell and Marshall butt heads on a work trip when their cut-throat business tactics don't align. Meanwhile, AJ turns down a request from Bell despite Mina's forewarning, Devon continues to gravitate to medical device rep Julian and the staff gears up for Conrad's three-year anniversary at Chastain.
Chastain is flooded with concert goers when a stampede at a music festival grounds leaves many in need of doctors. As Conrad and Nic race to help Josh Robinson, a professional adventure guide with a long list of prior injuries, Devon works with a musician who swears he is sober, even though his toxicology report suggests otherwise. Meanwhile, Bell stirs the pot when the hospital's revered orthopedic surgeon, Dr. Kit Voss, demands a better resident, Julian works to get her boss on Bell's good side and Winthrop continues to push Conrad to believe he's a changed man.
When Bell makes the executive call to utilize Julian Booth's medical devices, rather than the hospital's usual products, Kit and AJ must stop their momentary feuding in order to team up against him. Elsewhere in the hospital, Conrad and Nic work to make a child's dreams come true after finding out his cancer has returned and the rest of the staff takes notice of Julian and Devon's new friendship.
Halloween at Chastain proves to be just as spooky as ever when Conrad is tasked with diagnosing a young woman admitted to the hospital with extreme night terrors. Meanwhile, Devon faces his first Halloween in the ER, Nic panics over her decision to bring her newly sober sister to Mina's epic annual Halloween party and Bell finds an interesting way to make use of his new assistant.
When patients from the hospital's prescription drug trial start suffering life threatening side effects, Nic fears that her sister Jessie may be in danger. As a result, she and Conrad work to convince Bell that these trials are not worth the risk. Meanwhile, Mina, Austin and Kit must set aside their competitive nature and work together on a patient whose health is quickly deteriorating and Devon uses Julian as the beta tester for a product he's designed.
Conrad goes head-to-head with Bell after he recommends one of Julian's risky medical devices to Zoey, who's already lost one son and is back in the hospital with the other. Nic fears that Conrad may be getting overly attached to his patient. Meanwhile, Mina and Austin grow closer while working on a difficult heart transplant, Devon embarks on a very difficult day and Dr. Lane Hunter returns.
Devon's doubts about his relationship reach a peak as his friends and family gather for his big wedding day. As Chastain's leading medical device company, Quovadis, continues to succeed, Julian makes a discovery that leaves her uneasy about her involvement in it all. Meanwhile, Conrad continues to work on his relationship with Marshall and Bell takes a risky offer in order to make a mistake from his past disappear.
Lane Hunter's victims and their families become outraged when she is released from prison. Bell, although responsible for posting Lane's bail and getting her released, continues to be tortured by her manipulation. Meanwhile, Conrad uses work to cope with the news about his father, and he teams up with Mina, Kit and the Raptor to treat a patient who is suffering as a result of Lane's dangerous treatments. Then, Devon grows worried when he doesn't hear from Julian, and Nic sets her sights on a primary physician for their new clinic.
When a medical device fails on a former Chastain employee, an investigation is opened up, which pits Dr. AJ Austin against Quovadis. As Mina and Bell work to get to the bottom of what went wrong, Devon distracts himself with another patient who's experiencing mysterious stomach pains. Meanwhile, Nic forms a bond with her new partner at the clinic and Conrad's relationship with the Barnett family and continues to grow
When a nasty flu season turns out to be masking a terribly infectious disease, Chastain must race to quarantine and diagnose infected patients. Mina finds herself testing Quovadis medical devices in an effort to defend Dr. Austin, who, feeling responsible for the death of a patient, is serving penance by staying away from the OR. Conrad is prepared to take the next step with Nic, but finds that she may not be as ready.
Conrad, Kit, Mina and the Raptor work to save the life of a med student in need of a triple-organ transplant, drawing Bell back to the OR for one of the Chastain's riskiest surgeries yet. After the police find Julian's empty car in a nearby lake, Devon does some investigating of his own to find out what might have happened. Meanwhile, Mina and the Raptor hound Bell to halt his business with the risky medical device company, Quovadis, and Nic makes a rash decision regarding her sister.
When Conrad's attempt to surprise Nic with a lavish Valentine's Day dinner is foiled, he gives the reservation away to someone who could really use it. Mina and Devon distract themselves from all Valentine's celebrations by trying to figure out how their seemingly healthy neighbor has suddenly passed away. Meanwhile, Kit gives dating advice to a sex-injured patient, Irving hits a crossroads in his not-so-secret relationship with Nurse Jessica, and Bell decides to celebrate the day in the OR.
Bell's confidence in Quovadis continues to waver when the poster child for one of its medical devices, Henry Barnett, is rushed back into the ER, experiencing seizure-like symptoms. Meanwhile, Mina's past comes to light when her mother, famous Nigerian surgeon Dr. Okeke, pays a visit to Chastain, and Conrad makes a risky move when Henry returns to the hospital.
The surgeons are determined to shut down Quovadis after Henry Barnett almost loses his life due to a device malfunction. As Mina and Devon set out to find the truth, Bell, AJ and Conrad work to save the life of Chastain's favorite custodian, Simon. Meanwhile, one of Alec's old patients ends up in the ER, forcing him to question if he made the right choice to leave his old practice for Nic's clinic.
The surgeons work together to save the life of the Raptor's old mentor, Abe, who is their only inside source to Quovadis. Unfortunately, when Nic and Conrad take on a patient needing the hospital's only viable ECMO machine, they must decide between saving the life of Abe or saving the life of their younger, more stable patient. Meanwhile, Marshall puts himself in serious danger to help take down Gordon Page once and for.
Chastain picks up the pieces after the fall out with the corrupt medical device company Quovadis, leaving Marshall ready to charter new territory in the medical field, and Devon to finally discover the truth about what happened to Julian Booth. As Conrad and Alec team up to help a young gymnast experiencing mysterious symptoms, Nic focuses on her sister, who's back with their estranged father, Kyle, in tow. Meanwhile, Bell rushes to Kit's aid when her ex-husband comes to the ER needing emergency surgery.
When Atlanta is struck by a severe snowstorm, Mina must perform a big surgery - without the help of The Raptor - to save the life of a young father, while Kit and Bell get stuck babysitting the man's children. Nic and Conrad experience a disagreement with a patient's treatment, causing further strain in their relationship. Meanwhile, Devon teaches an important lesson about life and death to a first-year med student.
Devon grows concerned when a mother's complaints go unaddressed after her delivery, and pushes Bell to take drastic measures. Conrad is faced with breaking the news to Nic regarding Jessie's worsening condition. Meanwhile, The Raptor, Mina and Kit spring into action when a mother and son enter the ER with devastating injuries.
On his first day as an intern, an idealistic DR. DEVON PRAVESH faces the harsh realities of medical care, as third year resident DR. CONRAD HAWKINS takes him under his wing and teaches his unconventional ways for treating patients. Meanwhile, Conrad goes head-to-head with Chief of Surgery DR. SOLOMON BELL, who uses power and intimidation to cover up his mistakes.
Conrad receives the call he's been waiting for when a heart becomes available for a patient who has been on the transplant list for two years. But when a congressman is admitted to the hospital after a heart attack, he is prioritized and derails Conrad's patient's surgery. Meanwhile, Nic grows suspicious of one of the doctors after a file goes missing, Dr. Bell tries to manipulate Mina and Devon is put to the test when a patient's condition requires a split-second decision.
An old army buddy and fellow surgeon visits Conrad at the hospital. Meanwhile, the team is put to the test when they have to save the life of an uninsured and undocumented patient, while simultaneously battling the hospital's administrators, who fear the patient will cost millions. Also, Dr. Bell experiments with a new medication for his tremor and Nic swears to investigate the mystery surrounding missing medical records.
After a mix-up in the ER causes Conrad to deliver a death notification to the wrong family, he sets out to fix it. Nic struggles to find a patient's records who has been under Lane's care, Devon forms a bond with an elderly patient. Mina is benched after overreaching in the surgical unit.
Three concurrent surgeries at the hospital push its staff to the limits. Determined to ease the pressure, Nic requests Jude for one of the operations, making Conrad jealous. Dr. Lane Hunter sets out to discredit Nic's claims, Devon struggles with a patient who has an embarrassing problem and a charitable contributor comes to the hospital wanting to donate a lot of money to Dr. Lane's oncology program.
As Conrad battles a group of overly aggressive attending physicians on behalf of a patient with a mysterious chronic ailment, he also must face off against his father who has shown up at the hospital unannounced. When Mina goes out of her way to help a young man from her neighborhood who almost mugged her, Nic offers her assistance and discovers a secret that Mina has been keeping behind closed doors. While away from the hospital, Nic enlists the help of Devon to keep an eye on Lily, which leads him to an incredible find that has him questioning Dr. Lane's motives. Also, Renata's plans to poach a renowned surgeon from another hospital hit a standstill when Bell decides he doesn't agree with him.
Conrad goes head-to-head with Lane when he disagrees with her over a treatment plan for a terminal cancer patient. Tensions rise when Jude inserts himself in the middle by offering to perform the invasive procedure Conrad is fighting against. When a VIP patient crosses the line with Nic, she must devise a strategy on how to stand her ground and combat the situation. Meanwhile, Bell realizes he'll need Mina's hands more than ever.
Much to Bell's dismay, Nic and Conrad decide to admit a homeless Jane Doe, whom they suspect was dumped off by another hospital during Chastain's big Charity Ball. Elsewhere in the hospital, Devon and Irving care for a male escort who offers surprisingly good advice, Micah returns for a checkup and falls even harder for Mina, and Devon's parents are in town.
Conrad's ex-fiancé, Catherine, is admitted to the hospital with abdominal pain that proves to be quite the medical mystery. As Conrad doggedly tries to figure out her diagnosis and fights the idea of Bell performing her operation, Nic gets some insight into Conrad's past. Meanwhile, Bell panics when Claire announces that she will be installing cameras in all operating rooms, Devon wracks his brain for the perfect birthday present for Priya and Lane realizes that Nic is suspicious about her clinic.
Conrad is hit by a bike and badly sprains his ankle, but works through it when he takes the case of his old medical professor, who is hallucinating visions of her old patients. Devon is tasked with admitting Conrad, who refuses any sort of treatment. Nic tries to navigate her emotions while mourning the loss of a patient and Bell operates on a foreign dignitary with unforeseen complications. Meanwhile, Lane and Bell's relationship grows closer.
When Nic finds herself under investigation in Lily's death, Conrad comes to her defense, but ends up making the situation worse. During a routine surgery, Bell's patient accidentally catches fire, leaving the hospital to start an immediate investigation into his medical records. However, hospital CEO Claire Thorpe doesn't realize what she's up against when Bell plans a counter attack. Meanwhile, Devon deals with a series of ER patients, including a hypochondriac whom he fears could end up under Lane's care.
Conrad and Devon work tirelessly to save the life of Bradley, a fellow doctor who has fallen through the hospital skylight. As the team contemplates how and why he fell through in the first place, Dr. Bell looks back to when he benched Bradley for falling asleep during surgery. Amidst the madness, Mina is tasked with showing Chastain's new star cardiothoracic surgeon, Dr. AJ Austin, around the hospital, but is caught off-guard by his volatile personality. Meanwhile, Nic finds renewed enthusiasm when she uncovers an oncologist who used to work with Lane, but while paying him a visit, she fears that she's being followed.
Devon and Conrad race against the clock to save the life of a woman who is deteriorating fast from undetermined symptoms. When the patient turns out to be a hero who helps previous criminals get their lives back together, the team relies on her family of ex-cons to help diagnose and treat her. Tensions rise as Nic continues her search for evidence to incriminate Lane, but must simultaneously tend to her sister, Jessie, who is rushed into the ER. Meanwhile, York returns to the hospital with his mother, who is in need of a risky procedure, and comes face-to-face with the stone-cold Dr. AJ Austin.
In a final and drastic attempt to save Nic from Lane's acts of sabotage, Conrad must call in a favor from the one person he promised he never would. Meanwhile, Mina's partnership with The Raptor takes on new colors when Micah is rushed back to Chastain with major heart complications and Dr. Bell's alliance with Lane is put to the ultimate test when one of her patients is readmitted.