Gerard Butler – P.S. I Love You (2007)

This is one of the most disappointing entries on the list, because you would assume a Scottish actor like Gerard Butler could easily do an Irish accent. After all, the countries are right next to each other. To be fair, there are probably many Americans who can't tell the difference between a Scottish and Irish accent, but Butler's Irish accent was so off that even he addressed it in an interview with Irish host Paul Byrne of Movies Ireland, apologizing to the entire country of Ireland for his attempt at an Irish accent in P.S. I Love You.