Aside from the fact that this is produced by the LeCarre/Cornwall's own film company, The Pigeon Tunnel is hampered by its subject's tendency towards false modesty and purple prose.

Errol Morris' attempt to let his unreliable narrator a la Robert McNamara in Fog of War hang himself doesn't work so well here. While the film looks great, anyone familiar with LeCarre's books and life - which even Cornwall might admit is Graham Greene Lite - won't learn anything new.

You do get one kernel of wisdom - that intelligence agencies know about as much of anything as Hollywood studio heads. William Goldman would be pleased.

Even in his drugs, booze and alienating loyal consigliere and lover, Katy Haber, mode, Sam Peckinpah was capable of delivering great cinema. The production of this film was hampered by money problems and the director’s own demons, but its vision of war as man at his worst is searing. Its end credit sequence is chilling and arguably how Spielberg should have ended Schindler’s List, or why Kubrick couldn’t bear to make Wartime Lies in the end.