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 Bradley Freegard as Evan Howells Suzanne Packer as Delyth Lloyd Catherine Ayers as Lisa Connors Alex Harries as Arthur Davis Martha Bright as Angie Baldini 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 Dan Thomas as David Tate Mali Ann Rees as Dr Gwawr Sean Fletcher as Sean Jenkins QC Christine Pritchard as Professor Wynn