Al Capone became well-known for being a crimeboss in Chicago when alcohol was illegal.
这段话是说：阿尔·卡彭是芝加哥有名的犯罪大佬。
2
The IRA wants him back (he knows too much) and the local crimeboss, Meehan, will only help him if he performs one last hit, on a rival crimeboss.
IRA希望他(他知道的太多)，犯罪的老板，米汉，只会帮助他，如果他执行最后一击，在对手的罪行上司。
3
Nick fights to not lose his loved ones, while trying to stay in good grace with the very powerful local crimeboss. All the while, still trying to figure out who he is in life.