Who was Die Hard's Inside Man?

The film Die Hard is a staple in my house. I think I put the movie on at least once per month, though by this point it has mostly just been as background noise with me only paying attention during the highlights.

However, I put it on again last night and with nothing to distract me, did wind up paying attention to the whole film (or at least most of it). As I did, one thought popped into my head.

Who was the inside man working with Hans Gruber (Alan Rickman) and his gang of terrorists?

While the movie doesn't explicitly state there is someone withing the Nakatomi Corporation that is working with Gruber and his men, the evidence is there if you pay attention.

First, the security in Nakatomi Plaza is atrocious, to the point it seems almost by design. There is a lone security guard who doesn't check identification and a computerized directory that lists the names of everyone in the building. John McClane (Bruce Willis) was obviously the good guy in the film but could have just as easily been a bad guy who claimed to know Holly (Bonnie Bedelia).

And let's not forget John was there after business hours but was able to walk right in. Not to mention the loading dock was left open along with the parking garage. I know there were still people inside the building, but it did seem like someone was making it easy for Hans.

Holding a Christmas party on Christmas Eve is suspicious as well. I have gone on record calling Joseph Yoshinobu Takagi (James Shigeta) a villain for making his employees attend a company party when they should have been at home with their families. However, that decision makes sense when considered part of my inside man theory (though I have ruled out Takagi himself because he was the one person who could have just opened the safe for Hans).

For one, the plan needed hostages to work, and I can't think of a better way to keep people in the building after hours for that purpose. Having the plan unfold on the holiday also improved the chances of it working. Sgt. Al Powell (Reginald VelJohnson) almost drove away because he didn't want to spend the holiday investigating what he thought was a false alarm.

Hans and his men knew an awful lot about that building. There are only so many things you can get from blueprints and staking a place out. His team knew that building intimately, as though they were given a private tour beforehand. They also knew everything about that safe, from the contents to the various security features. 

That's not the kind of thing you're going to find out by looking it up on the internet, especially since the internet wasn't a thing yet.

Oh, and what was with that safe opening right up once the power was cut? This is something that has always bothered me, even before the inside man theory. I get cutting the power disabled the lock, but that thing swung right open, as though it was inviting the villains inside. It really feels like there was supposed to be another mechanism, a backup in case of power failure, that was disabled beforehand. 

Look, I'm not saying Hans wasn't a genius or even one of the best cinematic villains of all time. I'm just saying there must have been someone that wasn't brought to justice for their involvement for the crime. The evidence doesn't lie.

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