When three people are shot dead at a petrol station, Nikki and Jack strive to track down the sniper at large in London and stem a crisis.
| Name | Type | Role | |
|---|---|---|---|
| Ed Whitmore | Writer | ||
| Yvonne O'Grady | Guest Star | Mary | |
| Steve Wall | Guest Star | DCS Robert Drake | |
| Phil Cheadle | Guest Star | Conrad Devenish | |
| Max Wrottesley | Guest Star | Adrian Turner | |
| James Phelps | Guest Star | Chris | |
| Kathleen Fraser | Guest Star | Bertha | |
| Adam Wilson | Guest Star | Craig Cross | |
| Sean Gilder | Guest Star | DS Jim Clout | |
| Mabel Watson | Guest Star | Rosie Chamberlain | |
| Leemore Marrett Jr. | Guest Star | DC Howard Stent | |
| Robin Berry | Guest Star | Mark | |
| Jenny Ogilvie | Guest Star | Sheila Cross | |
| Sarah MacRae | Guest Star | Kate Hulton | |
| Veejay Kaur | Guest Star | Andrea Lakhani | |
| Jayne McKenna | Guest Star | Julia Chamberlain | |
| Simon Darwen | Guest Star | Journalist | |
| Zoe Telford | Guest Star | DCI Jane De Freitas | |
| Simon Desborough | Guest Star | Host | |
| Patrick Driver | Guest Star | Alec Smithson | |
| Daniel Qureshi | Guest Star | Steven Lakhani | |
| Martin Campbell | Guest Star | Alain Gontrard | |
| Stuart Laing | Guest Star | Martin Cross | |
| Sian Breckin | Guest Star | DC Gabby Lawson | |
| Simon Snashall | Guest Star | Graham | |
| Brian Duffy | Guest Star | Andrew | |
| Andrew Cooper | Guest Star | Joshua | |
| David Richards | Director |