James Nesbitt as Colin Howell, Genevieve O’Reilly as Hazel Buchanan, and Laura Pyper as Lesley Howell in the BBC One drama ‘The Secret’ (2016).
Main cast
- Colin HowellJames Nesbitt1Main
- Hazel BuchananGenevieve O’Reilly1Main
- Lesley HowellLaura Pyper1Main
Supporting cast
- DS Mark McTaggartJason Watkins1Supp
- DI Mark SykesGlenn Speers1Supp
- PC Jackie GillespieKaren Hassan1Supp
- Ethel BuchananStella McCusker1Supp
- Colin’s fatherLalor Roddy1Supp
Guest & voice
- Trevor BuchananConor Mullen1Guest
- PC WilsonJonathan Harden1Guest
- Molly HowellEnya Doherty1Guest
No matches — try another name.
About this cast
The Secret is a four-part BBC One drama based on the real-life murder case of Colin Howell and Hazel Buchanan. The lead cast includes James Nesbitt as dentist Colin Howell and Genevieve O’Reilly as his accomplice Hazel Buchanan, with Laura Pyper playing Colin’s wife Lesley.
FAQs
Who plays Colin Howell in The Secret?
James Nesbitt plays Colin Howell.
Is The Secret based on a true story?
Yes, it is based on the true story of the double murder committed by Colin Howell and Hazel Buchanan in Northern Ireland.
How many episodes are in The Secret?
The series consists of four episodes.
When was The Secret first broadcast?
It aired on BBC One in April 2016.
Who plays Hazel Buchanan in The Secret?
Genevieve O’Reilly plays Hazel Buchanan.
Sources & where to watch: IMDb · Wikipedia · Where to watch (JustWatch UK) · Updated June 2026