• Evidence
  • The security camera recorded Manaka as he seemingly waited for someone. Suddenly, with such agility and precision, the relic knight behind him struck with its sword. While it prepared to strike again, the owner barely managed to grab a painting tag, write something down and throw the pen away. The knight slashed and a final thrust ended his life.
  • Inspectors Megure and Kogoro found a museum staff's name, Kubota, written in the crumpled paper in Manaka's hand.
  • Bad as it was, Conan also found the pen on the floor;
  • And the bloodied suit of armor was discovered in Kubota's locker.
  • But then again, Conan noticed that the pen had its point retracted, the crumpled paper had inkless pen marks on it, and the artwork tags were in the room but the pieces weren't. Certainly, Kubota, who didn't seem to have a penchant for the arts, wouldn't have thought to protect those from being damaged.

• Conclusion

Manaka was scheduled to have a meeting with Ochiai, the art museum director. Little did the owner know that the director already staged his death. Ochia dressed himself with the suit of armor, strategically placed the tag with Kubota's name written on it and the pen with which Manaka apparently used to write the note, then murdered Manaka medieval style.

But the little eye of justice had tricks of his own. Conan pulled an "innocent" act of wanting the directions to the toilet be written by Ochiai. And before the director knew it, he drew the inkless pen from his pocket.

• Motive

In the hopes of getting the art museum to stay opened, the previous owner who got bankrupt sold it to Manaka. Manaka, however, was consumed by his own greed and planned to convert the building into a casino.

Ochiai was not going to let it happen as he considered the artworks as his own. He killed Manaka to prevent the inevitable.

And as for Kubota, Ochiai thought it just right to punish the person who had been selling some art relics and pieces secretly.