Spevak was responsible for designing Lucifer's new prison.
Background
Crowley ordered Spevak to re-design Nick's body so that once Lucifer possessed it, Crowley would have complete control over Lucifer. Once he had completed the task, Crowley killed Spevak to safeguard its secrets, which ensured no one could undo the system which contained Lucifer.
While Crowley was busy, Lucifer ordered a demon to find someone who could undo the system. When the demon told him about Spevak's death, Lucifer entrusted this demon to crack the system instead.
Appearances
- Season 12
- The British Invasion (mentioned only)