According to IMDB, Herr Starr and Sarah Featherstone will be in all of the episodes of Season 2. You can see the cast here. Pip Torrens is Herr Starr and Julie Ann Emery is Sarah Featherstone. This should come as no surprise to most as The Grail is a huge part of the comic books and this is the main focus of season 2 along with All in the Family in New Orleans.
Are you excited to see Herr Starr and Sarah Featherstone in Season 2, Episode 1?