Lugh is hired to assassinate Dia by her father Count Viekone, who is an old friend of Lugh's father Cian. Cian asks Lugh to fulfill Count Viekone's request, saying he'll carry out the assassination instead if Lugh turns down the job.
If you know all that, 
then that makes things easy.
إذا كنت تعرف كلّ ذلك، سيسهل الموضوع
Es vereinfacht die Sache,
wenn du davon gehört hast.
Que sepas tanto facilita las cosas.
Que sepas tanto facilita las cosas.
C’est bien que tu sois déjà
au courant de tout ça.
Se sai già tutte queste cose,
mi risparmi molte spiegazioni.
Se você sabe de tudo isso,
isso torna as coisas mais fáceis.
Раз уж ты всё это знаешь,
объяснить будет проще.