This audio is presented as a BBC programme containing a first person narrative by a man calling himself the Doctor. It is, allegedly, an hour long tape, made by the Doctor detailing his actions on board a pirate radio ship in the late nineteen sixties.
When he arrived on the ship he found Layla trying to make toast despite a power cut. To help this beautiful, blonde DJ he uses his sonic screwdriver to toast the bread, though he is surprised when she takes the device off him to spread the butter.
She asks him his name and he says he is the Doctor, a new DJ. She tells him he is lying: new DJs only arrive on Tuesdays. He confesses the truth, that he is tracking a weapon called The Hush. It was used in a war long ended but has been travelling on and arrived on Earth. He has followed it to the boat. He tells her it is a ball of vicious noise. Layla adapts well to this story and isn't even bothered by the Doctor's claim to be from outer space. She asks what damage The Hush can do. He says it can destroy the planet. When he realised it was coming to Radio Bravo he blew their transmitter to trap it on the boat.
Five minutes later Layla has introduced him to the other two DJs: Jasper and Tommo. His psychic paper tells them he is from the Pirate Radio Authority but he can't think of a believable reason from being there. Layla fill in for him saying that the oncoming storm is likely to destroy their ship. It could cause a ball of energy that will then be broadcast to the world and destroy everything.
Tommo is skeptical but asks what the Doctor intends to do. The Doctor replies that he intends to stop the energy ball from escaping. Jasper thinks it is all a ploy by the BBC to keep them off the air. Neither of the men is keen to help the Doctor but Layla enthusiastically helps the Doctor to hunt down The Hush. She asks what they are looking for but the Doctor says it can only be found by the profound silence that surrounds it after it has devoured all sound.
The sun sets. In the twilight they cross the deck. Layla asks why they can't leave in the Doctor's 'rocket'. He says there is a monster to be found and that is more fun than just leaving. The boat begins to rock in the approaching storm. They head below.
A patch of silence tells them they are on the right track. Then the corridor around them erupts into a clamor of noise. It is abruptly cut off by a scream. Layla says it came from Jasper's room. When they enter the room it is empty but Jasper is calling for help. Layla lifts a needle from a record player and the voice cuts out. She replaces the needle and the voice begins again. Unbelievably, he seems to be conversing with them, saying he is alone in the dark. The Doctor tells him he has been converted into a sound. He tries to reverse the process with the screwdriver. Jasper suggests they use the transmitter to boost the signal. The Doctor agrees that this might work but this would be what The Hush wanted. The Doctor asks Jasper what the last record he played was but Jasper can't answer the question. Layla realises that Jasper's voice might be The Hush. They notice that the record is a series of Jasper's jingles. It has been using his voiceprint.
They rush to the galley and tell Tommo that Jasper is dead. He takes this news with a pinch of salt and returns to the studio. Layla confesses that she is in love with Tommo and she only got a job on Radio Bravo to be near him, even though he hasn't noticed her.
Darkness falls. The screwdriver dies, eaten by The Hush. The Doctor leads Layla down a corridor towards the generator. They pass through a ball of silence while Layla tries to direct the Doctor. He is perplexed when her directions run counter to his memory, so much so that he barely notices her answers have become simple repetitions of things one or other of them said earlier. Instead of finding the engine rooms they go into another room. The Doctor realises he has left Layla in the dark and has been talking to The Hush.
The ship rocks in the dark in the storm. Layla realises that she has lost the Doctor in the dark. When she hears his voice calling her she makes her way towards him and bumps into Tommo. They find the Doctor in the darkness of studio 2 which is filled with banks of radio equipment. The Doctor tells them that the Hush lured him into a trap and he trapped it on a tape loop. He adds that they need to modify the transmitter and beam The Hush into space to get rid of it.
Tommo says that should be easy to manage. Control lights from the desk give off a faint glow as Tommo works and then Layla lights a candle. She tells Tommo that she can't see the Doctor anywhere. Something blows out the candle. Layla tells Tommo that the creature was there and Tommo nearly helped it destroy the world. She says the Doctor has gone. They hold hands in silence and listen to the storm outside. Layla says she is going to find either the Doctor or the generator. She relights the candle and sets out on her own.
She finds herself in a pocket of silence and follows a tiny tapping sound into another studio and finds the Doctor in a sound booth. He says he was hiding in there from The Hush. She explains she has just saved the world and how she foiled the alien weapon's plan.
Back in studio 2 Tommo is playing music by the light of many candles. The Doctor announces that he can see a way of getting out of this situation. He says they stay in the studio until daylight and play music. If The Hush attacks the sudden silence will alert them.
Tommo plays records through the night. At three o'clock Layla asks who made The Hush. The Doctor tells them it was an ancient race called into war for the first time in aeons. He describes the terror of its power at its height. Layla asks why the Doctor has made it his business to track it down and he seems to be on the point of telling her it was his own people that made it when he is interrupted by Tommo asking to go to the canteen. The Doctor refuses to let him go.
The ship sways in the storm while the Doctor fiddles with his screwdriver and Tommo plays records. Layla jerks awake from sleep and asks if one of them has been taken over while she wasn't watching. The Doctor tells her that The Hush couldn't keep human form for long. Tommo asks how they know that the Doctor isn't The Hush. The Doctor says he will get them through to the morning and then sink the ship. Tommo is aggrieved that they could leave in a time machine but not go back and save Jasper. Layla asks why they can't leave straight away.
Layla begins to poke fun at the Doctor travelling the universe on his own without friends. Just then she sees that Tommo has vanished. His voice is still in the room but his chair is empty. Layla begins to cry until Tommo's voice stops.
The two survivors sit in the dark in the storm. The Doctor promises he will take her away in the TARDIS when morning comes. She asks why the two of them are still alive but the Doctor can only say he doesn't know. Layla falls asleep.
This is the point when the Doctor records all of the previous narrative, mainly as a warning. It is then that he realises that The Hush chose Radio Bravo not as a refuge but as a trap. It needed the Doctor distracted but alive. He also realises that The Hush has been inside Layla all along and he was so close to taking her into the TARDIS.
Layla wakes up and the Doctor tells The Hush to use someone else's voice. It switches into the Doctor's voice as it explains that it has learned a lot from its victims and is now alive. It will carry on into the universe and keep on killing. This is when the Doctor tells it that he hasn't been sitting around talking for the last hour but has, instead been using his screwdriver to trap The Hush, bit by bit, on a piece of ferrous tape. He then says he will sink the ship in the storm. The Hush says that the tape will be found one day and that will e its chance to escape.
The Doctor says that he has left a warning on the tape so that nobody will play it to the end. Nobody could be that stupid. The Hush disagrees, saying that someone will inevitably play it, and then it shall be free.
The story ends with the sound of a tape running out..