Jennifer Mui is the most experienced member of ExOps, as she has been with the group for seven years. Jennifer previously worked as a member of MI6, the British national intelligence agency. Jennifer was born in Hong Kong to a Chinese diplomat, and a British attache. When Jennifer was ten, her parents divorced, and she moved to Britain with her father. However, she remained close to her mother, although the two were separated across two different continents.
When in Britain, Jennifer was alone for much of her time, as her father would be out for extended periods of time. This left her very self-reliant, and she excelled as a student and athlete. After graduating from schooling, she joined the Her Majesty's Armed Forces. When in the Armed Forces, Jennifer was noticed by an MI6 recruiter. While she enjoyed operating as a member of MI6, she was less than impressed with her income, causing her to drop out of MI6 and take an interest in becoming a mercenary. After this, she joined ExOps, where she operated for seven years, and helped to collapse General Choi Song's operations in North Korea
. This operation in North Korea later became known as the 'Song Initiative'. Jennifer is voiced across both games by Jennifer Hale
After her work in MI6, Jennifer has become the most stealthy operative in ExOps. Chris operates as a standard soldier, and is direct, while Mattias prefers to annihilate the target with massive firepower. Jennifer prefers to take the stealthy approach and snipe targets rather than engaging at closer range. Jennifer has been described by some people as being greedy, and she has a major obsession with money, after witnessing her mother's lifestyle after the divorce. Jennifer is very self-reliant, and does not rely on anyone apart from herself for the most part. Jennifer never questions the morality of her line of work, and believes that everyone is dirty - their money however, is clean. She enjoys operating as a mercenary, and finds that it allows her to be entirely self-dependent, and still provide the income required for the lifestyle she desires and enjoys living. Jennifer is a talented negotiator as well, and willingly manipulates clients who underestimate her.
Further evidence of Jennifer's love for material wealth is the car she is seen driving in the opening cutscene for Mercenaries 2. She is driving a Carbyne, which is one of the fastest cars in the game.
All three of the mercenaries across both games have unique abilities that the others do not. In the initial Mercenaries: Playground of Destruction
, each mercenary knew one language of a faction each, allowing them to translate their commanders for one faction. Jennifer speaks fluent Chinese, and is able to understand and translate the speech of the Chinese commander operating in North Korea. In Mercenaries 2: World in Flames
, Jennifer can run faster than both Chris and Mattias, echoing her athletic ability.