Britain has been listening to pirate radio since the 1960s and today it is reported that there are more illegal broadcasters than ever.
Former pirate DJ Trevor Nelson investigates the current scene.
According to official Ofcom figures, there are around 150 illegal radio stations in the UK today and 16% of London regularly tunes in.
The pirates argue they are an integral part of the British music industry and provide a community service that legal stations can't.
But broadcasting regulator Ofcom says the FM dial is full.
They claim the pirates are a problem, interfering with legal stations and the emergency service frequencies.
More worryingly, Ofcom says there is evidence of links to serious crime such as money laundering, guns and drugs.
Trevor revisits the world of illegal broadcasting to find out the truth behind today's pirate scene.
Now a presenter on BBC Radio 1, Radio 2 and 1xtra, Trevor began his career in the 1980s on the then illegal Kiss FM.
Trevor explores whether the scene has changed considerably since he was in the game or if the musical passion and spirit of pirates past are still present today.
Contributors include broadcasters, legal and illegal, a community radio station, fans, musicians, DJs and OFCOM, who were shadowed by the programme on a raid of a pirate station suspected of interfering with Radio 4.
Former pirate radio DJ Trevor Nelson investigates illegal broadcasting in the UK today.