Optimus was quiet as he checked over the scanners again, trying to make sure he was seeing it right. There was a ship, autobot by the energon signature, that just crashed outside of the city.

Agent Fowler was already on the ohone to get the site shut down for civilians, but Optimus just stared at the signature for a long few klicks.

“Optimus?” Ratchet asked, already preparing to head out to the crash site. “Your spaced out, what do you see?” He walked over and peered at the signature, trying to see if he recognized it.

“It’s nothing, old friend.” Optimus said smoothly, turning away from the console. “Ultra Magnus, Ratchet, and Arcee, come with me.”

—

The whole drive to the to the crash sight, Optimus’ processor was racing. He recognized the energon signature from both the ship and the mech inside of it, but he hasn’t seen that signature in vorns.

The last time he saw the mech that signature belonged to was at the siege of Iacon, when he watched said mech go offline.

Or so he assumed.

When the team arrived at the crash site, smoke still rose in thick plumes from the damaged vessel. A faint blue glow of leaking energon shimmered against the dirt, and the smell of burnt metal filled the air.

Optimus transformed, his heavy feet pressing into the ground as he surveyed the wreckage. He felt Ratchet’s optics on him, examining him even as the medic began looking for survivors.

“Whoever was onboard,” Ratchet muttered, his scanner buzzing softly, “their systems are faint. But they are still active.”

Ultra Magnus moved to the front of the wreck, prying open the twisted hull with a grunt. Arcee covered the perimeter, searching for Decepticon signals. But Optimus stood still, his optics fixed on the core of the ship where the energon signal pulsed weakly.

He recognized that frequency.

That specific resonance of energon had been imprinted on his spark long ago, someone who had once stood beside him as both a soldier and something more.

Ratchet glanced up. “Optimus?” he asked, his tone quiet and cautious. “You recognize this signal, don’t you?”

Optimus let out a slow, almost weary exhale. “Yes.”

Before Ratchet could ask anything else, Magnus tore open the last of the plating with a metallic groan. The group froze as the interior lights flickered weakly over the mangled remains of a cockpit.