A grieving father is convinced the police investigation into Lockerbie got it wrong.

Myles Bonnar speaks with Jim Swire, whose daughter Flora died in the explosion. He tells Myles he believes the real culprit is Iran.

Jim has always been outspoken about his theories. He claims his rising profile attracted unwanted attention from intelligence agencies, both in Britain and abroad. But what did they want with him?

Jim tells Myles about David BenAryeah – a supporter of the Lockerbie group who Jim believed was a member of Israeli intelligence agency, Mossad. But Myles knows him as someone very different.

Jim Swire’s not the only one who has doubts about who bombed the plane and why. The Lockerbie case has long been at the centre of a complex web of conspiracy. Myles speaks with a member of Abdelbaset al-Megrahi’s appeal team who tell him what they believe really happened in the months leading up to the Pan Am explosion.

Lockerbie is produced by Caitlin Smith

Additional production by Rob WilsonSound design by Eloise WhitmoreStory consultants are Innes Bowen, Jack Kibble White and Graham RussellFact checking by Faisal QureshiResearch by Rachael O’Neill and Callum McCulloch-NowlanOriginal development by Sally Greig LockwoodExecutive Producer: Gillian WheelanBBC Scotland commissioners: Heather Kane Darling and Victoria Easton-RileyFor BBC Radio 4, the commissioning executive is Tracy Williams, and commissioning editor is Dan Clarke.Music by Callan Marchetti