ented ▁young ▁painter ▁and ▁em otion ally ▁dist urbed ▁veter an ▁of ▁World ▁War ▁I , ▁first ▁introduced ▁in ▁the ▁second ▁book ▁in ▁the ▁series . ▁Ad ler ▁is ▁Hol mes ' ▁est r anged ▁son , ▁born ▁to ▁I rene ▁Ad ler ▁in ▁about ▁ 1 8 9 5 . ▁ ▁The ▁dist ra ug ht ▁Ad ler ▁see ks ▁the ▁couple ' s ▁help ▁in ▁loc ating ▁his ▁missing ▁wife ▁Y ol anda ▁and ▁their ▁daughter ▁Est elle . ▁ ▁Russell ▁and ▁Hol mes ▁separate ▁during ▁the ▁investigation ▁and ▁Russell ▁searches ▁out ▁Dam ian ' s ▁question able ▁past . ▁The ▁search ▁involves ▁the ▁British ▁pract ition ers ▁of ▁a ▁religious ▁cult ▁called ▁The ▁Children ▁of ▁L ights ▁with ▁roots ▁in ▁Shang hai , ▁China , ▁and ▁features ▁locations ▁r anging ▁from ▁Boh em ian ▁London ▁to ▁the ▁wild s ▁of ▁Scotland . ▁Russell ▁experiences ▁a ▁h arrow ing ▁trip ▁by ▁aer op lane . ▁A ▁series ▁of ▁bodies ▁appears , ▁some ▁dead ▁by ▁suic ide ▁and ▁others ▁rit ually ▁sacrific ed . ▁While ▁the ▁clim ax ▁of ▁the ▁novel , ▁in ▁an ▁ancient ▁circle ▁of ▁standing ▁stones ▁in ▁Or k ney , ▁brings ▁some ▁plot ▁resolution , ▁the ▁story ▁continues ▁in ▁The ▁God ▁of ▁the ▁H ive ▁( 2 0 1 0 ). ▁ ▁External ▁links ▁▁▁▁ ▁Category : 2 0 0 9 ▁American ▁nov els ▁Category : M ary ▁Russell ▁( book ▁series ) ▁Category : S her lock ▁Hol mes ▁past ich es ▁Category : Nov els ▁set