A formal biomimetic synthesis of (+)-hippolachnin A has been achieved under the guidance of its plausible biosynthetic pathway. Pivotal transformations include an intriguing 1O2-mediated [4 + 2] cycloaddition and a tandem Kornblum-DeLaMare rearrangement/hemiketalization/dehydration reaction. The current work not only offers a unified approach to access skeletally diverse plakortin-type polyketides but also provides convincing evidence to elucidate their underlying biosynthetic network.