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. Meanwhile, 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.

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 (guest star Malcolm-Jamal Warner), 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.

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.

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.

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 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. While Conrad, Nic and Alec work tirelessly on Meg, who was Nic's favorite guard from her stint in prison, Devon and the others treat Sam, a love-sick patient with flu-like symptoms. Mina finds herself testing Quovadis medical devices in an effort to defend Dr. AJ Austin, who, feeling responsible for the death of a patient, is serving penance by staying away from the OR. Meanwhile, Conrad is prepared to take the next step with Nic, but finds that she may not be as ready.

Conrad, Kitt, 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.