After a handkerchief is discovered near a murder victim, an inspector from Scotland Yard tries to track down the owner via the laundry mark on it. The next scene shows a commercial laundryman carrying a wicker laundry basket into a home. Outside the home, the laundry basket bears the number "T 31". Upon entering the home the laundry basket bears the number "T 14".
In Victor's room, two open newspapers are lined up on the rug. After his mother faints and comes to, the papers have changed position.
When Insp Conway wants to ring his office from the Colebrooke house, he dials just three digits, but gets straight through. If he'd dialled 999 (the British emergency number) he'd have reached an operator; he would have needed to dial seven digits to reach an ordinary landline.
Victor gives a false name to the other girls he kills, but tells Ann his real name. No explanation is given.