My life is a complex series of four-digit combinations...

ATM-card pins, Anniversaries, Birthdays, Library Cards. I try to forget outdated sequences, but somehow can't manage to erase them from the dark recesses of my subconscious, from whence they occasionally emerge, causing a great deal of confusion.
Outdated bank pin numbers, for instance are just a waste of memory space, unless forgotten. Sometimes, I remember the ATM code for my first ever bank card and not my present account. Is it written down somewhere? Of course not! That would be an affront my memory would not easily forget. But, there are clues camouflaged in my everyday life.

I can't remember the name of the movie - there's massive storage shelves and ladders in someone's mind, where all information is stored and frequently trashed to make space for new information. Sometimes, you want to trash memories that make you squirm, incidents that made you uncomfortable - but the harder you try, the more prominent they become in your conscious mind. As someone once said - You don't know where you're going unless you know where you're coming from.

The most complex four digit combination? 12 15 22 5