陕西西安邵家庄，庄主名曰邵华山。才高八斗前途无量，上至西安誉素王府，下至劳苦大众都对其敬爱有加。堂堂状元之才，却在翰林院任职一个小小编修，惨淡维生。然而，却没人知道他是华山秘派鹰蛇生死搏的秘密传人。
外星巨兽屁屁怪突然袭击地球大肆破坏，全球进入一级戒备，手足无措的军方决定向全球征集优秀的机器人设计，来对抗屁屁怪。梦想当发明家的麦兜（张正中 配音），也带着他设计的“电饭宝”去参赛，机缘巧合下，竟然侥幸当选。于是地球的希望，一下子都落在了麦兜身上！麦兜又能否成为英雄，拯救地球？
Ron Tayan now leads the 108 Dragons; Fu Ching Ran is his loyal wife. As their body tattoos show, he's the dragon, she's the tiger. The 108 Dragons are attacked by African Tusk, a syndicate intent on world control.
In a surreal world, a large maximum security prison, which houses thousands of dangerous inmates is run by an eccentric warden and his equally odd staff.
