Guest Stars Oscar Unsworth as Rhodri Howells Harry Unsworth as Rhodri Howells Mark Lewis Jones as Steve Baldini Hannah Daniel as Cerys Jones Eiry Thomas as DI Susan Williams Lacey Jones as Megan Howells Demi Letherby as Alys Howells Aneirin Hughes as Tom Howells Suzanne Packer as Delyth Lloyd Bradley Freegard as Evan Howells Catherine Ayers as Lisa Connors Alex Harries as Arthur Davis Rhian Morgan as Marion Howells Sion Daniel Young as Gareth Taxi Celia Imrie as Rose Fairchild Keogh Kiernan as Osian Matthew Aubrey as Mike Taylor Maria Pride as Julie Penry Siân Phillips as Judge Owens Marc Antolin as Professor Rhys Isaiah Cai Forrest as Lewis Kev McCurdy as Joe Price Rachel Cheung as Gym Manager