In Handan (the capital of Zhao), he met a merchant, Lü Buwei, who saw Yiren as extraordinary and detected in him the potential to become the king of Qin in the future.
In the meantime, through bribes and machinations, Lü Buwei helped Yiren return to Qin.
He also successfully conditioned Lord Anguo's primary spouse, the childless Lady Huayang, to adopt Yiren as her own son, thereby making Yiren become Lord Anguo's legitimate heir apparent.
As Lady Huayang was a native of the Chu state, she renamed Yiren to "Zichu" (lit.
He named Lü Buwei as his chancellor, Lady Zhao as his queen consort, and Ying Zheng as his crown prince.