Betrayal

Betrayal, parts one and two, are the ninth and tenth episodes to air in the twenty-second series of Silent Witness, and the 201st and 202nd episodes to air overall in the show. The episodes aired as following: Both parts of the episode were co-written by Virginia Gilbert and Michael Crompton, produced by Kiaran Murray-Smith and directed by Emma Sullivan. Richard Stokes served as the executive producer for both episodes.
 * Betrayal - Part One on 4 February 2019,
 * Betrayal - Part Two on 5 February 2019.

It is the final two episodes to air in the twenty-second series, and airs after episodes seven and eight of the same series: "Death Maker".

Part One

 * Judge Henderson - Gregory Floy
 * Lyndsey Morrison - Golda Rosheuvel
 * Dr. Nikki Alexander - Emilia Fox
 * Amanda Long - Dervla Kirwan
 * Kalan Dhanna - Manish Gandhi
 * Dr. Thomas Chamberlain - Richard Lintern
 * D.C. Vail - Adelle Leonce
 * Clarissa Mullery - Liz Carr
 * Max - Daniel Weyman
 * Jack Hodgson - David Caves
 * Alice - Kiran Sonia Sawar
 * D.I. Briggs - Ingrid Oliver
 * Richard Austin - Edward Franklin
 * Jacob Nduka - Leemore Marrett Jr.
 * Jenna Hong - Yennis Cheung
 * Arthur Pujari - Art Malik

Part Two

 * Dr. Thomas Chamberlain - Richard Lintern
 * Amanda Long - Dervla Kirwan
 * Leon Birchwood - Anthony Taylor
 * D.C. Vail - Adelle Leonce
 * Dr. Nikki Alexander - Emilia Fox
 * Clarissa Mullery - Liz Carr
 * Jack Hodgson - David Caves
 * Jacob Nduka - Leemore Marrett Jr.
 * Richard Austin - Edward Franklin
 * Jenna Hong - Yennis Cheung
 * Judge Henderson - Gregory Floy
 * Lyndsey Morrison - Golda Rosheuvel
 * D.I. Briggs - Ingrid Oliver
 * Alice - Kirwan Sonia Sawar
 * Barrister Delaney - Daniel Monks
 * Court of Appeal Judge - Nigel Fairs
 * Gavin Coulter - Simon Poland
 * Arthur Pujari - Art Malik
 * Barrister - Tasilimn Emiabata

Deaths
Two characters died across the two episodes.
 * Kalan Dhanna - pulmonary edema after being injected with trial drug tainted with succinylcholine.
 * Jacob Nduka - pulmonary edema after being injected with trial drug tainted with succinylcholine. Body then hanged from a warehouse beam to make it look like suicide.