Monday's episode of Lucifer Season 3 reminisced on Tom Welling's time playing the superhero Clark Kent in Smallville with a simple use of the word "Kryptonite."

Marcus' Kryptonite

Lucifer Season 3 Episode 13, "Till Death Do Us Part," alluded to The Man of Steel during a conversation between Lucifer Morningstar (Tom Ellis) and Marcus Pierce (Tom Welling). Marcus arrives at his office at the LAPD to find the devil sitting on his desk.

In the process of finding out what can kill the immortal Marcus (who is actually the fictional representation of Cain), Lucifer attempts to get the aloof lieutenant to open up about his feelings. Lucifer pretends to be a psychiatrist. At one point in their conversation, the devil uttered the word "kryptonite."

"How am I supposed to solve the mystery of how to kill you if I don't understand you first-your strengths, your weaknesses, because everyone has a kryptonite lieutenant," Lucifer explains when asked why he is going through all the trouble to help Marcus (see video below).

In the DC comicbook universe, kryptonite is the one thing that can kill the otherwise indestructible Superman. The use of the word kryptonite to refer to someone's weakness has become increasingly common over the years. However, Lucifer Season 3 Episode 13 clearly alluded to Clark Kent's Superman, given that Welling played the titular hero in the famous series Smallville.

Welling previously reminisced on his days as a superhero when asked why he took the role of Marcus Pierce in Lucifer. The actor admitted that it was a welcome change from playing Superman for several years. He also compared the two characters.

"The great thing about Clark is he didn't know who he was and he didn't know what he was supposed to do with what he had and his abilities. This character [Marcus] very much knows what he's capable of and knows what he wants to do and knows how to do it," Welling said.

Wolverine Easter Egg

Aside from Superman, Lucifer Season 3 Episode 13 also alluded to another immortal superhero — Marvel's Wolverine. Lucifer referenced the mutant comicbook character in his conversation with Marcus at Lux.

Still bent on trying to find a way to kill the lieutenant, Lucifer suggested cutting him in half with a chainsaw. However, Marcus explained that it would be futile since his cells would just regenerate and his body would heal or regrow by itself.

"If I cut you exactly in half would there be two Pierce's?" Lucifer asks in the video below.

"No, only one side would heal. You see I call that the master molecule theory," Pierce starts to explain before Lucifer interrupts and says, "Yes, yes, Wolverine rules I get it."

Lucifer Season 3 Episode 13, "Till Death Do Us Part," saw Lucifer and Marcus undercover as a gay couple to investigate the murder of a woman in a suburban neighborhood. Aside from Superman and Wolverine, the episode also alluded to K-pop, which stands for Korean pop. In the episode, however, it pertains to an illegal drug.