One actor was the star of three shows, The first one had a different title in the US from its title in the UK. The second one had the same title in both the US and UK, and it was the US title of the first show. The third was never officially called a sequel to the second, but it was, for all intents and purposes.
All remaining clues pertain to the third show.
Throughout the show, the star is menaced by "Rover" (not a dog).
The Butler (played by Maltese actor Angelo Muscat) never speaks, and appears in more episodes than anyone else, other than the star.
The show was filmed in the North Wales resort village of Portmeirion over the course of a year. The star was inspired to film his series there after filming a couple of the first show episodes in the village. The building in Portmeirion shown as the star's house in the series became a gift shop selling show-related merchandise.
Name the third show. For extra credit, name the other two.
George