Not long ago, The Flash and Arrow show runner Greg Berlanti told reporters that he hoped to get to crossovers between the shows and their characters sooner rather than later -- and today, the other shoe dropped.
The two CW series, based on DC Comics superheroes, will cross over for a two-hour event across their respective eighth episodes.
Assuming there are no skip weeks, that would place it at November 25 and 26 for The Flash and Arrow respectively. If there are programmed skip weeks, it would likely be in early or mid-December.
Barry Allen made his first appearance on Arrow in the second season's eighth episode last year, titled "The Scientist." That episode aired on December 4. The show's midseason finale, "Three Ghosts," continued that storyline and aired on December 11.
Executive Producer Andrew Kreisberg, who works on both series, said that most of the crossovers will be fairly low-key at first, but that this event is larger in scale.
"Episodes 8 of both shows, Arrow and Flash, are going to be a two-hour crossover event," Kreisberg told TV Guide. "[Also], in Episode 4, Felicity [Emily Bett Rickards] is going to come to The Flash."
Today, the network announced that Prison Break star Wentworth Miller will play Captain Cold in that episode, which will establish both his origin and that of the Rogues.
The Flash debuts on October 7 and Arrow comes back on October 8, on The CW.