Fresh testimony launches AC-12 back on the trail of the Caddy, a corrupt officer with links to organised crime. But new disturbing evidence suggests the Caddy may reside within AC-12.
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Timings (where shown) are from the start of the programme in hours and minutes
Line of Duty Finale
Do you know your OCGs from your UCOs?
Find out more about Lisa McQueen and John Corbett as they burst into the new series.