The 4th part of chapter 3 goes from page 134 to 149. A new confrontation between Kaga and Yasumasa!

• 濃紺・のうこん　dark blue
• 捺印・なついん　affixing a seal
• 兆候・ちょうこう　sign, indication, symptom
• 苛立つ・いらだつ to be irritated
• 口元・くちもと　the mouth
• 鑑識・かんしき　judgement, discernment. But I guess that here it means: forensics, crime lab
• ニキビ　pimple, acne
• 晒す・さらす　to expose (to the public)
• 繋がり・つながり　connection, relationship
• 経営者・けいえいしゃ　manager, proprietor
• 解剖・かいぼう　dissection, autopsy
• 手札・てふだ　one’s hand (when playing cards)
• 絆創膏・ばんそうこう adhesive plaster
• 導線・どうせん conducting wire
• 拍子・ひょうし moment, chance
• はがれる　to come unstuck from
• 胃腸・いちょう stomach, gastrointestine
• 迂闊・うかつ　careless, stupid, thoughtless

This part was an easy one, mainly because it was entirely composed of dialogues. Dialogues are much easier to understand than long descriptions…