Shaun struggles to accommodate the newest member of his surgical team, Charlie, who interferes in a patient’s relationship with his daughter. Elsewhere, Park tackles a tricky brain tumor, and Lea and Morgan adjust to motherhood.

Shaun continues to be tested by Charlie when their newest case prompts her incessant stream of questions – all in pursuit of an answer. Meanwhile, Morgan struggles on who to name as guardian for Baby Eden should anything happen to her.

Shaun and Lea struggle to balance their parental duties with their personal lives. Meanwhile, Park and Morgan try to find the time and space to reignite their romance amidst the demands of parenthood and work, and Lim's mother makes a surprise visit.

Asher's views on the construct of marriage complicate his future with Jerome. Meanwhile, Asher also briefly revisits his religious past to aid a patient's conversion to Judaism for his fiancée.

The team must deal with a mass casualty event that forces them to put aside their emotions following a recent tragedy.