There are Pretenders among us. Geniuses with the ability to become anyone they want to be.
Pretenders are a specific psychogenic type of human being whose combination of physiological and psychological factors allows for instinctive in-depth learning rarely available to human beings. As a result pretenders can very quickly master (and maintain on a sufficient level) any set of skills, with some being able to practically absorb behavior of any human being, providing for unique levels of understanding from both emotional and logical standpoints.
- 1 Physiology
- 2 Psychology
- 3 Known Pretenders
- 4 Appearances
- 5 Behind the scenes
- 6 References
The Pretender type is at least partially a result of inherited genetic anomaly, confirmable via blood tests. Most pretenders possess increased muscle memory, eidetic memory and honed senses (including peripheral vision) from early childhood.
To a certain degree talents of a specific pretenders could be at least partially successfully replicated via cloning.
Despite easily becoming social "chameleons" and generally possessing increased empathy, most pretenders experience problems with social adaptation. Even in adulthood they experience minor difficulties maintaining eye contact, opting instead for a fixed unfocused stare or increased eye movement.  
Depending on education and levels of stress experienced during formative years pretenders lend anywhere from relatively normal human behavior to complex post-traumatic stress disorder , extreme antisocial behavior and obsessive-compulsive disorders.
Due to specific talents a pretender can easily master any difficult set of skills to a degree of working knowledge or full professional understanding in weeks. While some tasks require over a month of preparation, in certain cases pretender can apply previous knowledge to synthesize necessary skills and/or behavior on the spot igniting no increased suspicion.
Most pretenders captured by The Centre since 1960's were used for advanced 'simulations', which provided assorted (at times military) contractors with working correct models of proposed operations or plans, as well as execution models. Pretenders are ideal consultants on any task given sufficient preparation time  and some could be found working successfully as actors.
Here is the list of known Pretenders:
Following persons are seen exhibiting partial pretender abilities and/or confirmed to have sufficient genetic material.
Behind the scenes
- Although existence of human beings capable of feats depicted in the series is confirmed in real life and was a partial inspiration for the series (specifically the case of Ferdinand Waldo Demara), there is no evidence that genetics has any sufficient contribution to such conditions and talents.
- Since the series are set in the same universe it could be theorized that Jack of All Trades on Profiler is a pretender.