The extraordinary call features in a Channel 4 documentary, The Home Counties Drug Cartel, which follows the Eastern Regions Special Operations Unit investigation into Brooks and his network

The phone call seemed typical of any loving father wishing a happy birthday to his young son.

Dad told the boy he was stuck at the office: “Have a lovely day,” he said “I love you to the moon and back, speak soon.”

But the man was lying. He knew they wouldn’t be speaking again for a long time.

That was because he was kingpin Robert Brooks and rather than being at the office, he was in Luton police station where he was being quizzed over a huge drug trafficking plot.

The extraordinary call features in a Channel 4 documentary, The Home Counties Drug Cartel, which follows the Eastern Regions Special Operations Unit investigation into Brooks and his network.