Bash's past weighs heavily on him as he fights for an emancipated teenager with a failing kidney. Mags treats a baby with a complicated heart condition. Theo is thrown by an asthma patient's brazen mother. After a patient makes waves, Dr. Bishop advises Bash to play it safe, while championing a new initiative in the York Memorial emergency department. June backs Dr. Bishop's proposal for a Trauma OR, sets boundaries with her brother, and tries to get a surgical patient to his wedding.

A city-wide blackout sends the hospital into total darkness. Bash treats a rock climber who fell from a cliff. Dr. Bishop and Bash make a major career decision, putting their futures on the line together. June is finally forced to face her father. Theo goes above and beyond to treat a deaf child, while letting frustration get the best of his spiralling personal life. Claire struggles to find footing in her new role as a nurse practitioner, and Mags pays a visit to a former mentor.