The matter had ended so quietly not because the other side lacked skill, but because this was merely an appetizer. They would use countless tiny ripples like these to raise a monstrous wave, until everyone was buried beneath the sea.
Sure enough, less than half an hour after the murder case ended, the Mercury Base terminal received an alert from its detectors: an alien spacecraft was rapidly approaching Mercury.
The base terminal had received no communication from the spacecraft and could not identify its registration code, so it dispatched defense drones to intercept it beyond the safety perimeter and did not allow it to approach Mercury.
Clark went to inspect the situation, only for the spacecraft to explode. It had not hurt him at all, but it still scared him into a cold sweat.
Humanity in the DC Universe had not yet entered the interstellar age, which meant they had no space-defense capabilities whatsoever and relied entirely on Mercury Base's security measures. If the defense drones had failed to stop the ship and allowed it to crash into Mercury before exploding, the casualties could have been severe.
The incident alarmed nearly all the upper-level personnel in the base, so the professors' group, which had disbanded less than half an hour earlier, gathered again.
The drones sent back the footage they had recorded. It was obvious that the spacecraft had not originated within the Solar System, and the writing inscribed on its fragments after the explosion was unfamiliar as well. For the moment, no one knew where the ship had come from.
Fortunately, the Justice League of this universe had ample interstellar intelligence support. They sent all the footage to Green Lantern Hal, who was working at Green Lantern Headquarters.
Hal quickly recognized the ship's information code as originating from Exo