During Bruce's early training in Batman Begins, one of the most memorable and visually striking sequences is a swordfight between Bruce and Ra's/Ducard on a frozen lake. This is a clear reference to the fact that Batman and Ra's have had several epic swordfights throughout the history of the Batman comics, most notably in 1972's Batman #244, where the two have a shirtless swordfight in the desert. Sure, the setting for each fight couldn't be more different and, as a result Bruce and Ra's are very much clothed in the movie version, but this comic panel is just too famous for it not to be the influence on the cinematic equivalent. Given how ridiculous the battle seems in the comic (Batman looks absurd still wearing the cowl), Nolan did a great job grounding it and making it seem less over-the-top. Wearing shirts is probably a big reason why.
Stay at home dad who spends as much time teaching his kids the merits of Martin Scorsese as possible (against the missus' wishes).
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