Mark was the mastermind

[Captain]

Please fix my passage.

Mark was the mastermind responsible for organizing and planning the US Mint robbery. He later oversaw the Federal Reserve of San Francisco heist, which had been orchestrated from London. As a cunning planner, Mark was able to control the entirety of the heist from behind the scenes, creating red herrings, and hoodwinking the police into doing exactly what he wanted them to do. There are only a few who could accomplish such remarkable feat, but his calm demeanor complemented his innate leadership traits, which allowed him to resolve any conflicts that arose without fuss.

 

[emsr2d2]

Please fix my passage.

Mark was the mastermind responsible for organizing and planning the US Mint robbery. He later oversaw the Federal Reserve of San Francisco heist, which [STRIKE]had been[/STRIKE] was/he orchestrated from London. As a cunning planner, Mark was able to control the entirety of the heist from behind the scenes, creating red herrings, and hoodwinking the police into doing exactly what he wanted. [STRIKE]them to do.[/STRIKE] There are only a few who could accomplish such a remarkable feat, but his calm demeanor complemented his innate leadership [STRIKE]traits[/STRIKE] skills, which allowed him to resolve, without fuss, any conflicts that arose. [STRIKE]without fuss.[/STRIKE]

First, I want to compliment you on your piece of writing. It is very good. With the exception of the missing article, it could have been left as it was. However, my changes above just tidy it up a bit.
In case it's not clear, the reason that I changed the order of the words in the final sentence is that it could have been (mis)read as "which allowed him to resolve + any conflicts that arose without fuss". Clearly, "conflicts that arise without fuss" isn't what you mean.