Watching movies usually puts me to sleep. Unless the movie is really exciting, it never fails, I end up sleeping through at least half of it.
The only way for me to stay awake is if I'm doing something constructive while watching. Knitting, sewing or drawing takes me through it. In the case of a drawing like this, it took two-three movies to finish, but I'm not in any hurry. Besides, I don't want to miss all the great scenes in an otherwise slow paced movie.