How The Crown's Elizabeth Debicki Embodied Princess Diana

Princess Diana had a few tricks up her sleeve ahead of her royal wedding.

According to the late royal's wedding dress designer Elizabeth Emanuel, she secretly made a second bridal gown before the then-20-year-old was set to walk down the aisle and marry King Charles III (then a prince) on July 29, 1981 at St Paul's Cathedral in London.

"The spare wedding gown was made just in case the secret of the real dress ever got out," the British fashion designer told Hello! in an interview published Aug. 5. "Fortunately, it was never used."

Elizabeth, who shared never-before-seen photos of the backup ensemble with the…