薛丁甲（陈豪 饰）和焦瑶（胡定欣 饰）结婚多年，共同养育着女儿薛思思（杨铠凝 饰），夫妻两人各自忙于事业，无暇顾及家庭及夫妻感情，随着时间的推移，整个家庭面临着巨大的危机。就在这个节骨眼上，一位名为妙妙（田蕊妮 饰）的保姆来到了薛家，担负起了照顾思思的职责。

　　没有人知道，妙妙的真实身份其实是薛家不久之前去世的宠物猫，她此番幻化成人，只为了报答薛家的养育之恩。在妙妙的帮助之下，薛丁甲攻克了工作中的难题，妙妙更是在误打误撞之中发现了一起针对薛丁甲的阴谋。一来二去之间，薛丁甲和妙妙之间渐渐产生了懵懂的情谊。

Planet Meow stars Kristal as Miu Miu, a cat-like alien from a distant, technologically-advanced planet. She looks after her beloved human master Sze Sze (child star Celine Yeung) from above. After watching Sze Sze suffer from her parents’ deteriorating relationship, Miu Miu decides to visit earth again to help her master, this time in human form.

Miu Miu, as a human, encounters the bone-setting master Ko Kwai (Mimi Chu), who hires her. By chance, she ends up working for Sze Sze’s father, Garfield (Moses Chan) at his research company. Miu Miu is protective of Garfield, and is aware that his superiors, Hill (Eddie Kwan) and Natasha (Vivien Yeo), have been plotting against him. Though Miu Miu works hard to fix Garfield’s relationship with his wife Cat (Nancy Wu), Miu Miu can’t help but to fall in love with him.