"Trog" is Wally Fawkes, the artist, who was also a clarinet player and a jazz band leader. Flook ran in the Daily Mail from 1949 to 1984 and began as a children's strip focused on a little boy, Rufus and his sort-of pet, a furry little creature that, in earliest days, could only make the sound, "Flook." It evolved over the years, scripted by different people, into a humor strip laced with political and social satire. The primary scripter was George Melly, and there's a wonderful write-up at the University of Kent's British Cartoon Archive.

This sequence, however, predates Melly's scripts and is a bit more of a kids' adventure strip.