One of Television's more interesting journeys has to be "The Fall and Rise of Reginald Perrin" a wonderful series about a man going through a mid life crisis. Reggie has a mundane life, a dull job, a doting wife and a happy family but one day he just begins to unravel. Reggie starts coming in late for work, he day dreams constantly (funny cutaway shots long before "Scrubs" or "Dream On") and begins lusting madly after his secretary.
The show just keeps twisting, with Reggie eventually faking his own death and becoming a pig farmer. He returns in the second season to his wife and opens a business intentionally bound for failure, a shop that sells useless items, it's a rousing success. He then hires idiots to help it fail and it becomes even more successful.
The third season has Perrin and his wife opening a commune of sorts and eventually has him returning to his life, dull job and all. It's exactly the sort of weird series that British Television nurtures and the American system tortures and kills, just due to their structure.
"Reginald Perrin" is a classic series and I wish there were more journeys like it.
There was a short run US version of this (called "Reggie") that I'll discuss at another time, I won't be gushing.