An Undertale twist on the classic "Jekyll and Hyde" Broadway musical. After having been rescued from the depths of the Void, Dr. Gaster resumes his role as Royal Scientist--alongside Dr. Alphys. Now that Monster Kind is no long in need of SOULS, Gaster sets out to begin studying the one thing Humans and Monsters have in common--good and evil natures. In believing it to be greatly beneficial to both races, the Doctor sets out on his new line of research. But, such a pursuit of knowledge can be quite the fine line, and crossing onto the wrong side can be disastrous.