cast in the same mold

Bearing a close resemblance, as in All his detective stories are cast in the same mold. This term uses the verb to cast in the sense of forming an object by running molten metal into a mold. [Late 1500s]

The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.