By their business structure, all banks are effectively zombies - in the sense that they commit fraud on day one by lending currency that you have kept in your savings or checking account which you might spend the very next day. When all transactions are kept in the electronic world (checks are in fact an authorization for an electronic transfer from your account to someone's else) - fractional reserve banking is beneficial to the bank with no visible impact for everyone else other than asset inflation. When the checks are sent from one customer to another of the same bank, nothing has changed at all for the bank. When one bank has more of its customers making checks or wire transfer (outgoing sum of currency) than incoming deposits from other banks, the interlending comes in and this bank needs to send this balance to the other banks. This is by the way, why there were $10,000 bank bills in the early 1900s to allow for banks to pay each other before wire transfers were available.
On average, this gets to be a wash, but on a few occasion, if a bank made too many bad loans that weren't repaid, their fractional reserve banking inverse pyramid became even narrower with a lesser currency base to support it. Although any banks would go under by just whispering "bank run", if one was more on the verge of running out of currency (that "liquidity problem" that Deutsche Bank CEO recently said they didn't have any worry about - or just like the CEO of Lehman Brothers in 2008), a self-reinforced zombie panic follows as the more customer withdraw this liquidity, the less the bank has. Oh sure, the bank has plenty of loans on their book to balance the currency they owe to their customers, it's just that they can't always ask for these loans to be repaid immediately. Oops
So what do I mean by a reference to Zombie movies you ask: a bank collapse spreads like a wild fever when the sum involved is too overwhelming for city's defense (think of that scene in Israel in World War Z) to be either bailed out or bailed in. If the "liquidity collapse" takes down a small regional bank, it can be contained as the sum is not overwhelming. Just as if the Zombie disease had been isolated to an island or an quarantine boat. But if a significant amount of the banking liquidity is affected and fast enough before the "authorities" have the time to steal - sorry to print - currency for the "greater good", then it is game over.
In this case, we have a dormant disease actually that has affected all major banks all interconnected. If one bank cannot pay back the other, the other bank in consequence gets a lack of liquidity as well and the dormant disease is awaken.
In some of these zombie movies, there is a reference to a cure. Unfortunately, there is no cure here other than letting this default to occur and restart with sound money with a formal abolishment of fraud (fractional reserve banking).
Even more unfortunately however, the politburo politicians will think they have a cure by stealing wealth from the population via a combination of bail-ins and bail-outs. Depositors will be seen as the blood required for a transfusion to the Zombie banks and obviously, that being not enough, huge amount of currency devaluation by a large infusion of bailout will follow. In other words, to maintain our analogy, after pulling out blood from large depositors, they will cut limbs from the general population by devaluing what's left of in their bank account and the cash under their pillow.
I have to admit that any nightmares the population might have had after watching I Am Legend or other Zombie movies will not have prepared them enough for the coming financial nightmare to be experienced.