Basically, this is a story that your big boss A kills your husband because he was not really happy with your career advancement and rather wanted you take care of the family. To ensure to make you work for A, A murdered your husband in the form of a traffic accident without any trace of the trick.
Meanwhile, A's deputy B hates A so much that B tries to kill you once A appoints you to the important position; on surface, A and B have been close friends since they grew up together and attended Harvard in the same class, but B has hatched longstanding rivalry toward A.
Your own deputy C assigned by B is the pain in the neck trying to prevent you from doing what you want to accomplish. He even made you gradually ill by inserting toxin into the coffee he serves you at the daily senior staff meeting. In fact, that was C's own way of saving you by trying to send you to the hospital, rather than allowing B to assassinate you in a high-profile event in order to demonstrate to the world that A's political ambition falls apart.
C managed to stop the assassination, and you decide to leave this incredibly dangerous position. You can no longer trust A and B, after all. Still, there is something you want to achieve in this important position and finally decided to stay, under the condition that C remains your deputy. Then B's body was found in DC.
