The paintings, hotspots and descriptions are detailed below. Note that keywords are in BOLD type
PAINTING 1 Man in a straight-jacket (LOS ANGELES)
PAINTING 2 Nurse at mental institution (MENTAL INSTITUTION)
PAINTING 3 Ackerman's doctor in LA (DOCTOR)
PAINTING 4 Chicago harbour (CHICAGO and HARBOUR)
PAINTING 5 Disturbed Sanctuary, victim in a bath
PAINTING 6 Gus and Ida - Ackerman's masterpiece
PAINTING 7 Apolina - there are also four hotspots (1) Apolina's eyes (2) Trees (WATER MILL) (3) Light blue area at the top (VLTAVA RIVER) (4) Red Drape
PAINTING 8 Frantiska below the bridge - there are two hotspots (1) Left side of the Charles' Bridge (BRIDGE) (2) Frantiska herself (3) The killer - near the bottom left
PAINTING 9 Street scene in Prague (PRAGUE)
PAINTING 10 Stephanie and angel statue
PAINTING 11 Body on the street near the sewers (SEWERS)
PAINTING 12 Man in prison cell
What do you know so far? The Chicago killer is a 'copycat' of the Perlovka Ripper in Prague. From studying the paintings you know the murders of Apolina and Frantiska have not yet been duplicated. The keywords triggered by these two paintings (WATER MILL, VLATAVA RIVER and BRIDGE) are probable locations the killer intends copying next.
Perhaps one of these locations in Prague shares a connection or common thread with somewhere in Chicago.
Using PRAGUE and CHICAGO as two of the keywords, try each of the locations as the third.
PRAGUE, CHICAGO, WATER MILL
PRAGUE, CHICAGO, VLATAVA RIVER
PRAGUE, CHICAGO, BRIDGE
One of the three produces the desired result - with an interesting connection to Gus' past.