Possible Clues:

• During every evening
• Nocturnally
• At the end of each day
• Each evening
• Sounding chivalrous when vampires prowl?
• By the sound of it, Sir Daly, no
• Each time it gets dark
• By the sound of it, the way for you, sir, every time it's dark
• Always before bed, say
• Irregular thing put on empty lorry at regular intervals