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Jekyll and Hyde

A person whose personality drastically changes between good and bad. A reference to the main character in the book Strange Case of Dr. Jekyll and Mr. Hyde by Robert Louis Stevenson. Ever since Kyle became a teenager, he's turned into a real Jekyll and Hyde, and it's impossible to anticipate his mood at any given time.
See also: and, Hyde, Jekyll

Jekyll and Hyde

someone with both an evil and a good personality. (From the novel The Strange Case of Dr. Jekyll and Mr. Hyde by Robert Louis Stevenson.) Bill thinks Mary is so soft and gentle, but she can be very cruel—she is a real Jekyll and Hyde. Jane doesn't know that Fred is a Jekyll and Hyde. She sees him only when he is being kind and generous, but he can be very cruel.
See also: and, Hyde, Jekyll

a Jekyll and Hyde

someone whose personality has two different parts, one very nice and the other very unpleasant
Usage notes: This phrase comes from the main character in the book The Strange Case of Dr Jekyll and Mr Hyde by Robert Louis Stevenson.
You can't depend on him to be friendly - he's a Jekyll and Hyde.
See also: and, Hyde, Jekyll

Jekyll and Hyde

A personality alternating between good and evil behavior, as in You never know whether Bob will be a Jekyll or a Hyde. This expression comes from Robert Louis Stevenson's The Strange Case of Dr. Jekyll and Mr. Hyde (1886). Also see lead a double life.
See also: and, Hyde, Jekyll
References in periodicals archive ?
Jekyll and Hyde goes out early on a Sunday evening.
I never thought I'd be cast in a period drama like this, but the wonderful thing about Jekyll & Hyde is how diversely it's been cast and the strength of the female roles," she adds.
Yet the parasite continues to act like Jekyll rather than Hyde in about 90 percent of the people it infects, living peacefully in the colon and producing no symptoms.
The 138-room Hampton Inn & Suites Jekyll Island opened in January 2010, the first new hotel to be built on the island in 35 years.
To commemorate this momentous occasion and reenact a landmark moment in time, the Jekyll Island Museum is hosting a "Centennial Celebration" this Sunday, Jan.
THE murderous tale of Dr Jekyll and Mr Hyde might not be everyone's idea of a jolly Christmas panto.
There have been more than 123 film adaptations of Jekyll and Hyde and a new Hollywood version is in production with Keanu Reeves in the title roles.
For everyday runners and beginners, the Turtle Crawl also includes a 5K race along the magnificent Jekyll Island shoreline.
Travel Business Review-January 17, 2012--Southeast Regional Sea Turtle Network announces Initial Meeting at Jekyll Island(C)2012] ENPublishing - http://www.
But, after opting for this remake of Robert Louis Stevenson's Dr Jekyll And Mr Hyde, she must have turned a queasy shade of green as roles she'd rejected won accolades for other actresses.
Henry Jekyll is a well-regarded physician whose evenings are spent researching a rare and sacred Amazonian flower so potent it is said to separate the soul, giving life to man's dark self.
However, Lavin disagrees with the Jekyll and Hyde description.
There were some false moments (a struggle between Jekyll and Hyde played out under strobe lighting looked far too comical) but it is a musical where the good elements finally triumph over the bad.