“I need five minutes,” he said.

Mara kept the door open. “You have them.”

Ellis noticed the blue fob lying on her bench. He stared at the notch.

“Where did that come from?”

“Why does everyone ask that?”

“Because Julian told me there was only one original control key left. He said the others were destroyed.”

“Number four wasn’t.”

Ellis stepped nearer, then checked himself. “I didn’t build that floor. I repaired the actuators. Julian brought me diagrams, a partly assembled console, and twelve motor modules. When I asked why the wiring didn’t match the drawings, he said the original inventor had been eccentric.”

“What did you find?”

“A signal combiner. A modern one. It can receive timing cues wirelessly from the lighting desk and route them to the motors. Julian said the mechanical movements were preprogrammed and completely safe.”

“Did he mention input five?”

“No. I found that label inside the cabinet. I assumed it was an original connector.”

Mara showed him the twelve-petal sketch. Ellis looked it over and reached for a pencil. He drew a line from the missing twelfth motor to an adjacent panel.

“That’s how the new system is wired,” he said.

Mara’s stomach tightened. “Two channels driving one actuator?”

“Through a combiner, yes. Julian said it would make the petal look fuller.”

“What’s the timing overlap?”

Ellis hesitated. “About four-tenths of a second at peak extension.”

“Could the motor hold both loads?”

“It can hold the load. Whether the old pivot can is another question.”

“And the emergency key?”

“Julian says the emergency controls are handled from the lighting desk.”

Mara shook her head. “So if the lighting desk sends a bad cue, the same desk is supposed to rescue the floor.”

Ellis sat on a toolbox, suddenly diminished. “I told him I wanted a mechanical disconnect.”

“Did you fit one?”

“I ordered it. He said delivery would miss the show, so we could add it next week.”

“Next week?”

Ellis lowered his eyes. “I came because I don’t want my name attached to someone getting hurt.”

“Then help us disable the motion channels in front of Ada.”

“He’ll fire me.”

“Probably.”

Ellis rubbed his hands together. “I have two kids and a mortgage.”

Mara resisted the urge to make a speech about courage. Instead she gave him the number of a regional stage engineering cooperative where she sometimes subcontracted. The foreman had complained about being short two technicians just last month.

“Call them,” she said. “Don’t tell them a heroic story. Tell them precisely what work you can do.”

Ellis pocketed the number. “I’ll meet you at the gym after three.”

“Why after three?”

“Because Julian’s shipping the replacement controller to the park at two. He doesn’t want anyone seeing it installed.”