A 14-year-old (Casey) leads his two half-brothers (H, 19 years old and baby Severino) on a journey to find and live as a family with his father after their mother dies.
| Actor | Role |
|---|---|
 Thomas Brodie-SangsterCasey | Casey |
| AAaron TaylorH | H |
| KKian SmithSeverino | Severino |
| CCory SmithSeverino | Severino |
| LLewis Ryan DickinsonSeverino | Severino |
| MMichelle AsanteVenetia | Venetia |
 Mandeep DhillonSeema | Seema |
 Aymen HamdouchiLenny Patrice | Lenny Patrice |
 Tim AhernAmerican Tourist | American Tourist |
 Nancy BaldwinAmerican Tourist | American Tourist |
 Ben BishopDi Douglas Turner | Di Douglas Turner |
| CClaire DisleyHome Carer | Home Carer |
 Kerry GodlimanLiz Walsh | Liz Walsh |
| SSimon JermondDavid | David |
 Radosław KaimMarek | Marek |
| GGeorgina LambSgt. Anne Riley | Sgt. Anne Riley |
| DDuncan MarwickBureau Teller | Bureau Teller |
 Brian McCardiePeter McBride | Peter McBride |
| EEric McNicholPolice Officer | Police Officer |
 Johann MyersBrandon | Brandon |
 Wendy PattersonA&E Receptionist | A&E Receptionist |
| PPaul WarrinerDoctor | Doctor |
| GGillian WaughPost Office Manager | Post Office Manager |
| AAmar AdatiaVikesh | Vikesh |
 Theo Barklem-BiggsMick | Mick |
 Iain CashYoung Police Officer | Young Police Officer |
 Paul J. DoveCoach Passenger | Coach Passenger |
| GGarth MaundersSmart Man | Smart Man |