What stands out particularly is the performance of Aya Sumika. When Sumika was brought on, her character felt plastic, cartoony, shallow, model-with-a-gun. Thankfully her "relationship" (if you can call it that) with Don was brief.
After that, the writers began to deepen and normalize the character. She looked and spoke less plastic.
With this episode, that process comes to surprising fruition. Suddenly Sumika shows that she really has some real chops as an actress. Her performance is very effective and (to use the overused word) compelling. She is understated, yet vivid, registering uncertainty, discomfort, anger, drive in a very dimensional manner.
The episode itself is worth the watch, but it's nice to see writers take a character brought in as a shiny distraction, give that character depth, and allow the actress a chance to do something other than look nice.