When Kellog "accidentally" meets Alec in the hospital, Alec asks him what he's doing there. Kellog replies "Uh, having a mole removed." This could be an in-joke directed at Rachel Nichols, who between season 1 and 2 had a skin tag (a benign growth) removed from under her right eye.
The drug "flash" enhances the user's perception in the same way as it's used by spaceship pilots on Andromeda (2000). A series where Lexa Doig features as the warship's avatar.
Brian Markinson (Inspector Dillon) and Magda Apanowicz (Emily) have both appeared in the TV show, The Magicians (2015) playing Everett and Woman from the Bar respectively. The episodes they both appeared in are, All That Hard, Glossy Armor (2019) and The Secret Sea (2019).