An explosion at Dell's house lands Betsey and Heather in the hospital. everyone is pushed to the limit in trying to save their lives.

The tensions between Addison and The Captain rise even more when her mother, Bizzy, shows up and a shocking family secret is revealed.

When Naomi refuses to help plan Maya's wedding, Sam convinces Violet to help her. Meanwhile the tension between Addison and Sam deepens when they treat a suicidal patient and Cooper and Pete treat a girl with a questionable bite mark.

Naomi begs Fife to use his still experimental treatment to help William's advanced ALS. Violet and Amelia treat a woman with a brain tumor, while Sheldon decides to vie for Charlotte's affections.

Sheldon counsels Sam's friend, Rick, an Army veteran suffering from PTSD who harbors a secret sexual trauma; Erica and Mason are involved in a car accident that forces Cooper and Charlotte to further come to grips with their future; Violet and Pete struggle to navigate life after marriage when he finds her kissing Scott; and Addison and Jake attend a medical conference they won't soon forget.