The Fixer (TV series)

The Fixer is an ITV drama that ran from 2008 to 2009.

Andrew Buchan plays John Mercer, an ex-soldier serving life for murdering his aunt and uncle after they molested his sister. One day, ex-cop Lenny Douglas visits him and offers him a release from prison...

If he becomes a government-controlled assassin who bumps off people the law can't bring to justice.

So he does, aided by small-time crook Calum -- an annoying but loveable sidekick -- and Rose, a former policewoman and Lenny's ex-wife.

Tropes used in The Fixer (TV series) include:

Anti-Hero: Calum's a Type I occasionally wandering into Type II, Mercer and Rose are Type IIIs, and Lenny's a Type IV frequently straddling Type V.
Black and Gray Morality: Mercer's hits are about protecting the Establishment and keeping British society stable, rather than punishing evildoers.
Bumbling Sidekick: Calum
Career Killers
Cliff Hanger: The ending of the second season.
Good Is Not Nice: Hot-tempered, coldly regimental Lenny all the way. Mercer, too, for the most part, though he has more Pet the Dog moments, mostly with Calum and his sister.
Honey Trap: Rose Chamberlain was thrown out of the police for trying this tactic to snare a rapist, which was deemed "entrapment". She continues to do so however to gather information for the unit, much to Mercer's distaste.
Latin Lover: Manuela
Morality Pet: Mercer's sister.
Plucky Comic Relief: Calum
Rogue Agent: In one episode Mercer is ordered to kill his predecessor, who has started to pick his own targets instead of those selected by Lenny. On another occasion an SAS man who (under orders) used drug money to finance his anti-Taliban operation decided to go into business for himself.
UST: Between Rose and Mercer. Calum often lampshades this.