When his mother leaves, seventeen-year-old guitarist Mick O'Brien is desperate to buy back the family piano that his father hocked. His attempt to get the money looks grim until an all-girl rock group, Total Fire Band, arrives in town for the annual harvest season. When they advertise for a replacement female lead guitarist, Mick dresses up in his mother's clothes and successfully auditions for the job. Complications arise, however, when he falls for the lead singer, Angela. Jilted by one too many lying men, she in turn finds herself confusingly attracted to this new 'female' member of the band.
The storyline calls for a number of 'live' performances from both Total Fire Band and Barry's band, for which Mick also plays lead guitar.
According to director/screenwriter Gerard Lee, the process of getting All Men Are Liars onto the screen was a ten-year project. Difficulties in raising the required finances also led to him eventually taking on the role of first-time director.