It's easier to hide Easter eggs in action-adventure shows than most other genres as viewers are too busy taking in all the ongoing events to make note of clues thrown around. Interestingly, many shows in this genre actually get creative with small details, with things like references to real-world facts, foreshadowing, and plot connections. There are also instances where certain mistakes may escape notice of the shows' editors and fans on the internet have caught on to these as well.
Here are small details about action-adventure shows that you probably haven't seen before.
In Justice League S2E12 (2005), an Alternate Universe Superman lobotomized all of the inmates of his Arkham Asylum. But with the Ventriloquist, not he himself but his puppet Scarface has the scars.
In season 12, episode 15 of Supernatural, ‘Lucille’ the bat wrapped in barbed wire that was used by Negan in The Walking Dead makes an appearance as one of John Winchester’s favorite weapons. Both John and Negan are played by Jeffery Dean Morgan.
In 1x07 of The Flash, Barry Allen is the victim of an attempted mugging. That same mugger (but with sh*ttier hair) attempts to rob Barry and Ralph Dibny (Elongated Man) in 4x06.
In Arrow - "Salvation" (S01EP18), Laurel's mom says she should be in Central City in a flash. One year later, Barry Allen appears in one Arrow episode and The Flash got his own TV show.
