We report on the wrenching of a metal-capped periodically corrugated polymer bilayerwhen the bilayer is annealed at a temperature far above the glass transition temperature ofthe polymer layer. Certain corrugation geometries such as several micrometre line width ofgroove and ridge and step heights, thicknesses of the metal film, and extents ofreduction of the elastic modulus of the polymer layer by increasing the annealingtemperature give rise to a wrenching pattern in the metal surface. This wrenchingpattern was characterized by the critical wrenching angle. The critical wrenchingangle could be theoretically determined by calculating the mechanical energyrequired for the wrenching of the metal film and polymer layer in order to relax thethermal compressive in-plane stress. An increase in the annealing temperatureincorporated with a decrease in the corrugation period yields a smaller criticalwrenching angle. For the critical wrenching angle larger than a certain value, thewrenching wave pattern was directed by the wave interaction relationship between thecorrugation and the intrinsic buckling wave of the metal-capped polymer bilayer.