The promo for the latest episode of CBS medical drama "Code Black" has been released, and it promises an event that will shake the staff of Angels Memorial Hospital to their core.

In the trailer for Episode 10, "Cardiac Support," senior nurse Jesse Salander (Luis Guzman) suffers a massive heart attack, leaving the emergency room rattled.

Now Dr. Leanne Rorish (Marcia Gay Harden) will be tried as never before, as she is forced to save the life of one of her dearest friends.

It seems unlikely that the show will kill off such an important character as Jesse, especially so soon after its debut. Such a major plot development would no doubt mark a significant change to Leanne's character, who already has experienced so much heartbreak in the past. Still, nothing is ever certain in television, especially in a hospital drama where the prospect of death seems ever present, even if the core cast is usually immune.

This tragic event could also help strengthen the relationship between Dr. Neal Hudson (Raza Jaffrey) and Leanne, who often butt heads due to Leanne's sometimes rash medical decisions.

"You think he's all you have, but you're wrong," says Neal to Leanne in the promo. "You have all of us."

The episode synopsis also says first-year resident Mario Savetti (Benjamin Hollingsworth) will ask his colleagues to cover for him as he searches Los Angeles for a patient's son, in direct opposition to Neal's orders. It should be interesting to see more of the world outside of the ER.

Fans should be seeing a lot more of Angels Memorial emergency room, as CBS has ordered five more episodes of "Code Black," bringing Season 1 to a total of 18 one-hour installments, Deadline reports.

Catch the new episode of "Code Black" on Wednesday, Dec. 2 at 10 p.m. ET on CBS. Check out the trailer below!