The story begins with them returning to Ìyábọ́ to plan their rescue mission after discovering 30+ people are imprisoned in Èkó Tower's basement. They successfully contact Táíwò again through the 99.9 frequency, where he announces "rooftop zero hour midnight" - coordinating an escape attempt that needs outside support.

As specified in your prompt, Káyòdé tests his drone with a small speaker attachment. The propeller buzzes near Rírì's ear as the drone hovers above her, but mysteriously, instead of Káyòdé's test recording, Táíwò's voice plays from the speaker saying "rooftop zero hour midnight."

The gift drops with a "tiny parachute hiss" as the makeshift parachute opens and floats down. Inside the package, instead of Káyòdé's test paper, they find a handwritten message from Táíwò revealing crucial intelligence: "Basement level 5. Thirty-two people. Them dey use us to create anti-sorrow frequency. Midnight escape through ventilation shaft to rooftop."

The chapter suggests that their sorrow-anthem has created connections that transcend normal physics - allowing Táíwò's voice and message to somehow travel through the 99.9 frequency and manifest through their drone equipment. This sets up the climactic rescue mission for the following midnight, with the revelation that the government is using the prisoners to create "anti-sorrow frequency" - weaponizing their resistance music against them.

The story follows their plan to use Ìyábọ́'s frequency detector to locate the exact source of the 99.9 signal where Táíwò and other missing people are being held. While Káyòdé creates a distraction with false signals, Rírì hides inside a blue rain barrel to get close enough to the tower for accurate readings.

As specified in your prompt, the rain drums "bùm-bùm-bùm" on the barrel surface, creating both cover and tension. Aṣàkẹ́ whispers updates through her radio while her teeth chatter from fear and cold as she watches for security.

The suspense peaks when a security guard's boot steps stop right beside Rírì's barrel. The guard stands there for what feels like eternity, his flashlight beam dancing around the barrel opening while rain continues drumming on the plastic surface. Only increased distraction from Káyòdé's false signals draws the guard away at the crucial moment.

The chapter ends with the revelation that the frequency detector picked up signals from 20-30 people in the basement, not just Táíwò. This escalates their mission from a single rescue to a mass liberation operation, raising the stakes significantly.

The rain barrel becomes both literal hiding place and metaphor for the precarious position of their resistance - protected by thin walls while surrounded by overwhelming force.

The story follows their return to the abandoned clinic where Ìyábọ́ reveals a secret room containing a massive vintage radio from the 1960s. As specified in your prompt, the radio knobs make "click-click" sounds like bones cracking as she adjusts them, creating an eerie atmosphere in the old x-ray room.

Ìyábọ́ tunes the radio to frequency 99.9, which she calls the "sorrow-ghost channel" - a frequency that shouldn't exist but somehow carries voices of missing people. When they hear Táíwò's voice coming through the static, describing being held in a dark place with strange machines, it confirms he's alive but imprisoned.

The chapter reveals that the government's jamming technology has accidentally created a bridge between dimensions of sound, allowing voices from Èkó Tower's basement to leak through radio frequencies. They hear fragments suggesting the authorities are conducting experiments with "backwards music" - possibly trying to reverse their sorrow-anthem for control purposes.

Aṣàkẹ́ wonders if Táíwò is somehow speaking "from inside" the radio, though Ìyábọ́ explains it's more about electronic interference creating unexpected communication channels.

The chapter ends with them receiving a frequency detector to help locate the signal source and the revelation that multiple people are being held for mysterious experiments at Èkó Tower's basement levels.