In Chapter One, Enfield recounts Hyde’s assault of a child and the limited amount he knows about the mysterious perpetrator. Utterson asks Enfield why he never asked anyone for more information about Hyde, and Enfield replies that questions are always the start of trouble:
“You start a question, and it’s like starting a stone. You sit quietly at the top of a hill; and away the stone goes, starting others; and presently some bland old bird (the last you would have thought of) is knocked on the head in his own back garden and the family have to change their name.”
Enfield's speech foreshadows the unraveling of Jekyll’s life and reputation as Utterson begins to ask more questions about his relationship with Hyde. As Enfield warns, Utterson’s investigation begins innocently enough; he sits “quietly at the top of a hill,” merely asking after the safety of a beloved friend (Jekyll). But as the story goes on and one question leads to another, the last person anyone would have suspected is revealed to be a disgrace.
Given that Enfield knows that Jekyll is connected to Hyde in some way (thanks to Jekyll’s signed check), this warning to his cousin has interesting implications. In the most direct sense, this line insinuates that Jekyll specifically may be hiding something, or that Enfield has heard something about Jekyll that Utterson hasn’t. Enfield hasn't yet revealed to his cousin the name of the person who signed the check, but he subtly suggests that respectable figures, even those who seem trustworthy (“some bland old bird”), are often the objects of the greatest intrigue. This impression is heightened by Enfield’s snarky characterization of Jekyll as someone who “doe[s] what they call ‘good.’” With this remark, this instance of foreshadowing also anticipates the revelation of Jekyll’s true, hypocritical character at the end of the novella.