disease treatment
doctor
dramatist
face
fiend
hate
hide
homicide
illness
infection
invasive disease
invention
inventor
love
mask
masked ball
masque
medical facilities
medical treatment
murder case
murderous
mystery person
opera
phantom
phantom of the opera
plague
plague bacillus
plague doctor
public performance
rat
revenge
stalker
teatro dell opera
theater
theater festival
theatrical company
tragedy
tragic
true character
ugly
unrequited love
white