The first thing we heard at 7:55am on Monday was not the usual bell. It was a beat. A real, bassy one, with such an entrance that even Mrs Genowefa from the canteen raised her head from above the pot of porridge, as if someone had thrown a bluetooth speaker in. And immediately afterwards a voice rang out - warm, slightly hoarse, as if leading a late-night radio show. "Good morning, Maria Skłodowska-Curie High School No. 2 in Zawilec. Please do not run. If anyone is running, I doubt it's towards success." We stopped in the corridor of the second C class. Rose, who had hitherto fastened her glans on two loops at once, blinked. - Does our bellboy have a sense of humour? - she whispered. - 'Looks like it,' said Kamil, already taking his phone out of his backpack and firing up some app that he claimed was 'for spectrum analysis'. In Kamil's case, everything had a spectrum: of sound, of light, and probably also of his mood. I'm Lena. We run the school newspaper 'Periscope'. In practice, that means we get free plastic T-shirts for papers and a discount on tonic in the library, because Mrs Zosia thinks tonic is printer ink. The voice returned at break time after the first lesson. This time he began: "Ladies and gentlemen, today physics at nine o'clock. I would like to remind you: gravity does not take holidays. If anyone was planning to drop a grade, let them do it from a low height." Laughter spilled like tea over the bench in the biology room. Even Mr Marek from P.E., who can only recognise a joke if it is thrown in the form of a medicine ball, snorted. Headmistress Nowicka did not parry. She left the office like a ship that cuts through waves of smiles and leaves behind a foam of sticky notes. - Mr Henryk! - she called out to the caretaker. - Radio. Immediately. Who started it? And WHO changed the bell signals? Mr Henry stroked a bunch of keys like a cat and tapped it against his hip. - Director, I didn't trigger anything. That's what it says," he replied philosophically. 'At Periscope we had a meeting as early as the second break. There was too much going on to ignore it. - 'It's the perfect topic for the issue,' said Rose, scribbling a sketch of the headline 'The bell has a voice' on the blackboard with a marker. - 'We'll investigate the source,' said Kamil. - 'The radio is in the room next to the music room, but nothing new there. I suspect an eavesdropper, plugged into a line somewhere. Or a signal from outside, plugged into the old installation. - Simpler - I interjected. - Or one of the students has decided to turn our everyday life into a steam engine of chatter. The voice returned every break, commenting gracefully on everything from a lost avocado sandwich ('Green UFO found. Witnesses please contact us') to a maths competition ('Reminder: natural numbers don't have feelings, although they behave as if they do'). There was a kind of benevolent irony that doesn't hurt, but makes the day something more interesting. Around midday, a note came to me. Pushed through a crack in the door of the Polish room, folded into an airplane. I unfolded it. The letters looked like they came from a typewriter, black and even: "Leno, Kamil. If you want to hear the real bell ring, be at 6:18 p.m. at room 13. Take a banana." - Ban... what? - Rose recoiled as if a grasshopper had emerged from the leaf. - Let me guess," said Kamil. - Symbolism. A banana like a smile. Or a radio code. Or... just someone wants to make a banana in our pocket. - A banana in the pocket is made by everyone who goes to the canteen for fruit,' muttered Rose. - Are you going? We went. At 6.18pm the corridors are as quiet as a jar of nails - nobody wants to open them. The lights came on and off with a slight slip, as if the school was taking an inhale and exhale. Room 13, the 'History Workshop', had long yellow blinds and a display case with a green Legionnaire's cap. As we approached, a speaker flicked on from the ceiling, and then we heard it: "Thank you for your punctuality. The corridor behind room 13 leads to the stairs down. There, please hand the banana to the authorised person." - Authorised person? - I whispered. - If it's an orangutan, I'm going home," said Kamil. - But it's cool. I have two bananas. One in case the authorisation needs to be shown in duplicate. I rarely saw the stairs behind Room 13. They led to a corridor that smelled of dust and parquet varnish - a forgotten part of the school. The door at the end had a sign saying "Boiler room - after renovation. Do not enter." Who wouldn't want to enter, right? Before we could touch the handle, however, Mr Henry slid out from behind the map cupboard. - And you for what reason? - He looked at us with the matter of the Inner Handle Inspection. - By virtue of the social contract. We help distribute the fruit,' I fired out, before my brain thought it was a bad idea. I pointed to a banana. - An order for an authorised person. Mr Henry looked at the fruit, then at us. He sighed. - 'The headmistress has a conference today, so she can't see anything. But if I see you pulling out something you shouldn't, then... - he hesitated. - 'Then I'll call up Mr Mark and he'll make you guys do the twats until matric. - We understand - Kamil bowed. He exchanged a banana for a brief nod from Mr Henryk that looked like a stamp. The door creaked as he opened it. The boiler room after the renovation was a boiler room without a boiler. What remained were pipes, some cables, metal shelving and the smell of concrete that still remembered the footsteps of the foremen. In the corner stood a cork board with a note taped to it: "MEMORIES OF THE RADIATOR". Someone had attached a drawing of a heart to it with a paperclip. - 'And now the technique,' Kamil whispered, as if someone here was about to catch him quoting a textbook. He took a small box with a flashing diode out of his backpack. - 'Since the voice is going over the radio, we should hear a slight buzzing of the line. If there's an extra transmitter, I'll detect. More or less. - I'm afraid of the more or less,' I admitted. - But I like them. We put our ear to the wall. The buzzing was there. Even, steady, like the breathing of a sleeping monster. Somewhere up above, the alarm standing by the escape door wailed, but only for a second, as if it had gone off. - 'It's somewhere closer to the stage,' Kamil said at last. - The radio station has a switchboard behind the auditorium. If anyone has tapped in, it's there. The auditorium in our school was older than anything. It smelled of chalk and an old curtain that someone wanted to wash ten years ago, but gave up after reading the tag. We went down through the backstage area. A backstage area is where all the things that couldn't make it elsewhere stand: three mannequins, a prop-chandelier, a paint bucket and a model of the solar system, which was now more like an arrangement of independent planets housed in an orange carton. - Do you hear? - I asked. For a moment, between one beep and another from Kamil, I thought I heard something. Like a flutter. Like the sigh of old microphones when someone runs a finger over the net. - 'There it is,' Kamil confirmed. - It's the wire. It goes into the hiding place behind the old desks. He pointed to an iron door in the wall, so low you had to bend down to look in. "Telecommunications switchboard" - informed the sign, which still remembered the days when the word "teletechnology" sounded like a promise of cosmic adventure. The handle was cold and reluctant. I pulled harder, my forearm trembling. Kamil pressed together with me. The door gave way, creaking like the hinges in an under-oil fable. Inside was something I hadn't expected: a tangle of cables, but arranged. On each cable a sticker with a letter and a number. On the shelf was a mug with the words "Best Sound Realist" on it. In the mug - fresh traces of coffee. Someone had been here. Not long ago. Next to it was a box of headphones, a mixer manual, and finally a metal case, the kind you cart instruments in. The case was locked with a combination padlock. - 0-0-0-0? - I tried. - I begged, we were learning about combinatorics. - Kamil spun the dials with the face of a mathematician who had finally found a use for a trigram. - Look at the stickers. The letters are like a plan. D1, D2... It could be a date. Or the time. - 1-8-1-8? - I asked, feeling the voice along the corridor come back, as if someone had carried it in a pan - warm and ready. - After all, it was in the letter. - That would be the dumbest and best code in the world - Kamil smiled. He turned the wheels. 1-8-1-8 He tried to lift the padlock. It snapped, but... it didn't break. - Too bad - I muttered. - Almost like a movie. Before we had time to try a new number, a voice rang out. The same as in the morning, only closer, as if sitting next to me backstage, wrapped in a black curtain. "Microphone test. One, two, one, two. Watch out for the reverb. Kamil, don't touch that red plug or I'll talk through the canteen. Leno, inhale, exhale. Your heart is beating faster than a 120 bpm pace." We froze. We looked at each other, at the cable, at the coffee cup, which still seemed warm. The voice continued, quieter this time, almost a whisper: "If you have made it all the way here, it means that you hear more than just sounds. You also hear the things in between. I'm starting a programme just for you in a minute. Don't be late... because I'm starting with a song you don't want to miss." The lights on stage left flicked on for a second and a single, solitary lamp came on, projecting a circle of light onto the boiler dust like an island on a map. Instinctively, Kamil reached out for the padlock. - One more try,' he whispered. - 'Maybe it's not 1818, but...' - Wait - a voice interrupted him. - Before I start, I have one question. I felt the skin on the back of my neck run with electricity. The voice made a short pause, so precise that I could hear something ticking in the auditorium, maybe the old clock in the history room. Then the unfamiliar, smiling radio voice, right next to me, said: "Leno, Kamil... are you ready to hear who's been talking to you all morning?".