Zhang Yizhi (張易之) (died February 20, 705), formally the Duke of Heng (恆公), nickname Wulang (五郎), was an official of Wu Zetian's Zhou Dynasty who, along with his brother Zhang Changzong, became a lover of Wu Zetian and became very powerful late in her reign. Both he and his brother were killed in a coup that overthrew Wu Zetian in 705.
Read more about Zhang Yizhi: Background, As Wu Zetian's Lover, Death