When Shifu's ex-girlfriend, Mei Ling, visits the Jade Palace, Po decides to try and get them back together, despite the fact Mei Ling is now Shifu's most hated enemy.
In "Shifu's Ex", years after Shifu's and Mei Ling's break-up, Mei Ling visited the Jade Palace, claiming that she wished to redeem herself. Shifu was hesitant to trust her but his honor permitted her to stay in the Jade Palace. And later that night, on Po's encouragement, Shifu visited her in her room, wanting to apologize. This soon led to a kiss, before Mei Ling used the Zhou Deng Soul Gem to switch bodies with him. She locked Shifu in the dungeon while posing as him, planning on exploiting Po and the Furious Five to robbing an Imperial convoy transporting precious jewels, thereby damaging the honor of the Jade Palace warriors and forcing Shifu to get back with her.
However, Shifu was able to escape and managed to convince his students of Mei Ling's treachery. They go back to confront her, when at the same time, the Imperial Army was banging on their door, convinced they were all traitors. Shifu then tricked Mei Ling into a kiss, all the while swiping the Soul Gem to put both of them back in their proper bodies. It is then revealed that Shifu and company were able to clear up their misunderstanding with the Imperial Army, who had been faking a siege. Though Mei Ling was confident that Shifu wouldn't harm her, he pointed out that his students would. Mei Ling later escaped custody while going to Chorh-Gom Prison.