Playable characters

Playable characters from the Theory of Nicole series.

Forever playable characters

 * The ten-foot atomic-powered plankton
 * Sophie the Otter
 * Catherine the Spellcaster

Ongoing playable characters

 * Nicole Birou-Jennings (Theory 2-present)
 * Planktonine (Theory of Nicole-present)

Former playable characters

 * Jo Frost (Theory of Nicole)