Over the course of a year I tend to try five or six new TV shows. Like everyone else I have a finite amount of leisure time and I therefore try to split it evenly among my various interests. Overall, I watch no more than ten shows regularly. I like to do some research before selecting something new to watch and I also consider recommendations from my peers very important. Once I’ve decided upon what I shall try, I tend to give each new show a fighting chance to build up a head of steam. Not all shows hit the mark immediately. Some need at least half a dozen episodes. Some need several seasons. So far Designated Survivor has proven gripping and well-conceived. It also doesn’t make the usual mistake that densely-plotted dramas so often do, in continuously taking one step forward and another two back.