S6, E11: After learning that Percival’s (guest star Chris O’Shea) plan to reinvigorate Riverdale would lead to the demise of Pop’s, Tabitha (Erinn Westbrook) searches for a way to fight back. But when she is targeted by one of Percival’s accomplices, the incident sends her back in time and searching for answers. KJ Apa, Lili Reinhart, Camila Mendes, Cole Sprouse, Madelaine Petsch, Mädchen Amick, Casey Cott, Vanessa Morgan and Drew Ray Tanner also star.