Behind the scenes, "Crisis on Infinite Earths" is underway. Even as the Arrowverse builds towards the major crossover on screen, its cast and crew are busy filming the event itself, which means its biggest stars have some unique insight into the story. Armed with this knowledge, Arrow star Stephen Amell dropped a piece of cryptic "Crisis" dialogue."Crisis On Infinite Earths Dialogue Tease," he wrote, then dropped this bit of dialogue: “Yes & No... [it's] complicated.”RELATED: Crisis on Infinite Earths: First Photos of Ashley Scott's Huntress Surface

Since Amell provides no other context, it's hard to guess where this line of dialogue fits in. However, since he is sharing it as a tease, it must be significant to the plot in some way. As it stands, we know his character Oliver Queen will die, but it's hard to say how this would relate to that. Further, Arrow star Katherine McNamara -- who plays Oliver's daughter Mia -- heavily suggested their characters will meet, so perhaps this dialogue has something to do with their family reunion.

"Crisis on Infinite Earths" begins Sunday, December 8 at 8 pm ET/PT on Supergirl, then continues in Batwoman on Monday, December 8 at 8 pm ET/PT and in The Flash on Tuesday, December 10 at 8 pm ET/PT. After the winter hiatus, the crossover will conclude on Tuesday, January 14 in Arrow at 8 pm ET/PT and in DC's Legends of Tomorrow at 9 pm ET/PT.

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