LINE Of Duty fans are convinced hated DS Patricia Carmichael is the shadowy 'H' after tonight's explosive episode. At one point she hammered her pen on the desk four times - spelling out 'H' in Morse Code.
Morse Code is an alphabet that spells out words or messages - for example the distress signal 'SOS' - using a series of short and long sounds.
But by tapping out four short sharp raps on a table, as Carmichael did, it indicates the letter 'H'. The criminal mastermind - known only by the single letter - has long been thought to be at the heart of police corruption on the BBC show.
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