Jekyll and Hyde
Jekyll and Hyde describes someone who behaves kindly at one moment and cruelly at another, as though they were two different people; it comes from the story of a doctor and his dangerous other self in Robert Louis Stevenson’s Strange Case of Dr Jekyll and Mr Hyde.
Where it comes from
The doctor and his other self
The phrase comes from Stevenson’s story of a respected doctor who uses a drug to become Edward Hyde. His attempt to separate his good and evil impulses ends in a loss of control.
In Strange Case of Dr Jekyll and Mr Hyde, Jekyll goes to bed as himself but wakes up as Hyde, although he has taken no drug that night.
In The Strange Case of Dr. Jekyll and Mr. Hyde by Robert Louis Stevenson
What it means now
Today, the phrase points to a disturbing contrast between someone’s pleasant and unpleasant behaviour. It usually suggests more than an ordinary change of mood.
In Strange Case of Dr Jekyll and Mr Hyde, Jekyll welcomes his friends to dinner, while Hyde brutally attacks Sir Danvers Carew. The contrast helps explain the phrase’s force today.
In The Strange Case of Dr. Jekyll and Mr. Hyde by Robert Louis Stevenson
How to use Jekyll and Hyde
- Use it for a sharp contrast between kind and cruel behaviour.
- Explain which actions reveal the two sides.
- Avoid using it as a label for a mental health condition.
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Are Jekyll and Hyde actually the same person?
Yes, Jekyll and Hyde are the same person in Stevenson’s story. In Strange Case of Dr Jekyll and Mr Hyde, the doctor takes a drug that changes his body and allows him to act as Hyde, before the changes begin happening without his choice.
Does Jekyll and Hyde mean a split personality?
In everyday speech, it means sharply contrasting behaviour, not a medical diagnosis. Someone might use it about a person who is gentle in public but cruel at home. Applying the phrase to a mental health condition can be misleading and hurtful.
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