In this week’s instalment of our series tracking cinema’s worldwide winners …• Warner taps into patriotism untouched by previous war-on-terror films• Seventh Son banking on Slavic film-goers’ fantasy fetish• Birdman shapes up as another indie breakout for Alejandro González IñárrituFirst things first. In a world of success preordained through marketing and omniscient data tracking, it’s nice to be blindsided and bamboozled by an actual box-office surprise.