When the brilliant Dr Jekyll desires to indulge his dark side yet remain a respected proper gentlepony he at first tries to continue his strange and kinky relationship with the musical pony Octavia however when even his relationship with her being leaking out of his household the Doctor uses the depths of Science to give him a new form so he can continue to be with Octavia while remaining a proper aristocrat in front of the rest of society. However as his dark side is fed it grows in strength and Dr Jekyll soon becomes unable to control it leaving his friends to try and unravel the mysterious case of Dr Jekyll and Mr Hyde.