I'm a huge crime fan, Sherlock Holmes, Agatha Christie et al. Columbo is head and shoulders above all comers. Such a clever premise of seeing the murderer at the start and watch Columbo snare his man (or woman). Columbo is a genius. But it only works with a suitable villain. jack Cassidy is my favourite but there are so many real stars making an appearance (check them out). True, the later episodes don't compare to the pinnacle of the show but every episode is worth a watch (or 2, or 3......)
Just one more thing.......