show someone a good time
Entertain someone, as in I know Aunt Dorothy will show us a good time when we visit San Francisco. This idiom uses the verb show in the sense of “accord or grant something,” a usage dating from about 1200.
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.