TBH, when I saw the test footage of this film, I thought this was cancelled. However, it was done and released only in Spain and the United Kingdom.
Dogtanian And The Three Muskehounds is a remake of the classic 1980's Spanish-Japanese cartoon that is based on the 1844 classic tale, The Three Musketeers, the movie is basically a retelling of the series, starting with Dogtanian and his father's duel. After defeating his father, he earns the family heirloom, the Omega Sword, and is sent to Paris to become a Muskehound, only to team up with three of them, Anthos, Porthos, and Aramis, as well as Juliette, a lady in waiting Dogtanian falls in love with, and Pip, a mouse thief who becomes his squire, to save France from an evil plot from Cardinal Richelieu, who aims to sieze the throne by starting war between France and England.
Now, this may not be a film for everyone who grew up with the original cartoon. There are new voice actors (and whoevers voices Dogtanian is good, but not as good as the legendary Cam Clarke, the original English voice of the hero), and it does add characters not seen in the original (like Pip, who can be found as annoying), but it does a good job with the story (adding in more details and even some 2D scenes that look like the original series updated). I recommend watching this and coming to your own conclusion, but I see it as a good film in my book.