Hellboy eventually tracks down Klempt to his laboratory .
After making his way further into the castle , Hellboy encounters an undead soldier who tells him the castle was built by the Nazis to carry out their experiments , with Klempt returning to finish his work .
Hellboy eventually tracks down Klempt to Klempt 's laboratory .
After making his way further into the castle , Hellboy encounters an undead soldier who tells him the castle was built by the Nazis to carry out their experiments , with Klempt returning to finish his work .