Rebecca Ryan has been working as an undercover agent for the Organised Crime Division (OCD) posing as a taxi driver, while investigating London's south-side mob. When she finds her young daughter Lynn brutally murdered she fears her cover has been blown wide open, so she turns renegade and begins a brutal campaign of vengeance against the mob she believes killed her daughter. As she trawls the seedy depths of London's underworld hunting down her daughter's killers, the lines between good and evil, right and wrong begin to blur as do her notions of justice and revenge. It falls to the world-weary OCD agent Darius Cuise and his newly-assigned, hot-tempered partner Abby Barrett to track down Rebecca and bring her in before all hell breaks loose.
| Actor | Role |
|---|---|
 Claire GooseRebecca Ryan / Margaret | Rebecca Ryan / Margaret |
 Donna AirAbby Barrett | Abby Barrett |
| AAnthony OfoegbuDarius Cruise | Darius Cruise |
| GGeorge CalilHarry McCann | Harry McCann |
 Riana HusselmannMarla McCann | Marla McCann |
 Victoria BroomAmy Morgan | Amy Morgan |
 Sarah HardingJade Jennings | Jade Jennings |
 Robbie GeeBenjamin Radcliffe | Benjamin Radcliffe |
| TTom BaconTrigg | Trigg |
| MMarlon KerrArron White | Arron White |
 Ben ShockleyMr. Ward | Mr. Ward |
| SSadie TonksMrs. Ward | Mrs. Ward |
| OOlivia Glynn-JonesLynn Ryan | Lynn Ryan |
 Cyril NriRestaurant Manager | Restaurant Manager |
| DDominic DebiasTristan Jarret | Tristan Jarret |
| BBailie JamesBilly Hills | Billy Hills |
| MMatthew ReynoldsTom Curtis | Tom Curtis |
 Kjersti Helen RasmussenCandy | Candy |
 James PaytonTodd Marker | Todd Marker |
| FFrank HellebrandChopper | Chopper |
| SStuart RennieRobbie Ward | Robbie Ward |
 Dominic GlynnPoliceman | Policeman |
| JJames BoylePoliceman | Policeman |
 Keith EylesDavid Cummings | David Cummings |