The following contains spoilers for Moon Knight, Episode 4, "The Tomb," now streaming on Disney+.
One of the most intriguing aspects of Moon Knight is the dynamic between Marc Spector/Steven Grant and Layla. While Marc is married to her, she's connecting more with Steven over archaeology, especially because she's bitter Marc left her high and dry. It caused tension and jealousy between Marc and Steven, because, ultimately, Marc abandoned her to protect her from becoming Khonshu's next avatar.
However, the latest episode confirmed there was more to Marc's guilt, diving into a key death in Layla's life. This revolved around her dad, Abdullah, with Moon Knight finally spilling the beans on Marc's secret: he inadvertently caused the man's death.
The bombshell was dropped when Layla and Steven tracked down Arthur Harrow's cult at the tomb of Ammit in Egypt. While the villains tried to free the vindictive goddess, Steven and Layla had to escape a mummy, which resulted in them separating in the catacombs. Layla ended up killing the creature, only to find Harrow condescendingly paying tribute to her.
When she called him out for being a monster, Harrow maintained she needed to check those around her because they were untrustworthy. Harrow then confirmed Marc killed her archeologist father in a heist gone awry. Deep down, part of Layla felt it was true, especially due to Marc's secrecy in the past, plus everything with them just felt like coincidence.
She ended up confronting Steven, which resulted in the Marc personality emerging, admitting Harrow's words were partially true. It turns out Marc's mysterious partner was the one who got trigger-happy in the theft, shooting and killing everyone. The person even shot Marc, leaving him for dead, which allowed Khonshu to broker the deal with Marc to become his avatar. It left Layla upset, wondering if she could trust the man she married. Layla didn't believe him when he said he tried to find a way to tell her and that he was scared it'd ruin their love.
This opens a Pandora's box, with fans wondering if Marc did have a partner or if it was another of his alters -- whether it be Jake Lockley or someone else. This further explains why Khonshu would see Layla as a possible Fist of Vengeance, knowing she'd have a lot of rage to harness and people to punish..
Lastly, Abdullah's death may tie into why Marc's fractured mind possibly latched onto the Indiana Jones-like Steven from the movie, Tomb Buster, in the asylum shown in the finale. Marc may have picked it up had he done a stint there in the past, developing the British personality to assuage his guilt over Abdullah's death. Ultimately, Abdullah's murder at the dig site isn't something Layla will forgive easily, so the remaining episodes of Moon Knight will have to find Marc making huge strides if he's to garner a second chance over something that has haunted Layla for years.
See how Layla and Marc rebound from this bombshell in Moon Knight, with new episodes available Wednesdays on Disney+.