Jekyll-Hyde Syndrome

The outbreak began in southern England in 1885. Fortunately, manifestation is quite rare; less than 0.00005% (about one in 24,000) of the general populace show symptoms. It is believed that the majority of the population carries the virus, but very few suffer its strange effects.

In GURPS terms, Jekyll-Hyde Syndrome grants a character the Split Personality disadvantage with the aberrant personality possessing approximately 60 points in mental disadvantages and reduced IQ (and, usually, a couple levels of reduced Appearance) and a more-or-less equal amount in physical advantages and increased ST and DX (and, often, a few levels of Fearlessness).

There is a medication which reduces the chances of the aberrant personality surfacing; Antihydazine. The drug gives a +3 (to a maximum effective IQ of 15) to resist the change to (but not from) the darker persona. It costs $8 (or £1 12s.) per dose (about 6 cc's) and lasts 4 days. Someone who uses this regularly to control their changes would have to apply a -20% limitation to the points gained from Split Personality (and not just the base -15). The cost of the drug, per month, is $60 (£12). (The limitation value is reduced because of the high cost of the medication; only those with wealth levels of Comfortable and higher will be able to take the drug regularly.)

"Vector zero" for the disease was Dr. Henry Jekyll, who was also its creator. In January, 1889, his aberrant form, Edward Hyde, committed suicide, thus ending both their lives. The full story of Dr. Jekyll's affliction was related in a book by Robert Utterson, Jekyll's lawyer.

"There is a demand in these days for men who can make wrong appear right." — Terence