Xia Luo is married to Madong Mei, but is still in love with his high school crush, Qiuya. On Qiuya's wedding he decides to get drunk and sing to Qiuya a love song. Madong Mei is not very happy with his behavior and attacks him. Xia Luo runs away and hides in the toilet.
But when he leaves it, he is back to his high school days... And now he has a second chance. What will he change? Will he 'conquer' Qiuya's heart?
The story is not to be taken too seriously (even if we actually get a couple of serious moments), and we can see the ending coming from almost the very beginning. But the plot is not really what matters in a time-travelling comedy. A story like this is perfect to be acted and directed with silliness in its heart. That the story is simple and self-centered around Xia Luo could be forgiven if it was funny and with a frantic pace. However the laughs come and go, and the pace is too uneven. That without forgetting that it has a couple of worrisome moments, starting with Xia Luo's penchant to sexually harass Qiuya after he has traveled back in time (even if he believes it is a dream).
"Goodbye Mr.Loser" is a not very original comedy, worth a couple of chuckles, but that is also way overacted and with problems of pace. A middling effort.