Remember “Crooked Skyscraper”, “Russian Cafe”… These all have the same bent effect, more commonly known as “Cafe Wall Effect”. It gives you impression lines in the wall are all messed-up, while in fact they are perfectly straight & parallel. This image below shows you the original Cafe Wall that inspired the use of it’s name for all other illusions of this type. I’m not sure where it’s located so your help is needed…