Michelle is the wife of Sam Hanna and the mother of his daughter. She is a CIA Agent who has returned to work after caring for her family for an unknown period of time. She met Sam eight years ago while they were working on a mission at the task force.
Michelle has been featured in limited appearances on the show, the latest being Episode: Wanted where it was revealed that she is once again working for the CIA.
She did not resign even if she put her career on hold. She is back in the day when her character Quinn is the only one capable of approaching a rotten Russian diplomat who put their hands on a nuclear bomb. The case is on hold, but allowed Michelle to realize that she still loves her job, to the point of not wanting to be sure to take her place as a mother and wife when everything is finished. Sam is very concerned about the situation.
Near the end of Episode: Descent she was pushed out of a high building and left hanging during a fight with the Russian girls. During an undercover operation she and her husband were sent in in order to foil Isaak Sidorov's plan and capture him. As Kensi Blye arrived at the scene, Michelle dangled from a balcony, but managed to free herself and help Kensi against the Russian girls.