The CW is interweaving all of their superhero shows. Just as they’ve done with “Arrow” and “The Flash,” “Legends of Tomorrow” will cross over with both shows, but the midseason drama won’t wait until the winter to start the crossover fun. Plotlines will be introduced on “Arrow” Season 4 and “The Flash” Season 2 that serve as prequel storylines for some of the heroes.

"Both Arrow and Flash are helping to set up those things, in both big ways and small ways, which is lovely," producer Andrew Kreisberg said at a Television Critics Association press conference, according to the Hollywood Reporter.

Kreisberg also revealed which characters will show up on which show. It looks like the characters will stick to the dramas they were introduced on: “The mystery of what happened with Palmer (Brandon Routh) is playing out on ‘Arrow.’ Sara Lance (Caity Lotz) will also be playing out in the first seven episodes. ‘The Flash,’ we obviously have Firestorm and Martin Stein (Victor Garber) and Ronnie Raymond (Robbie Amell). And Kendra Saunders (Ciara Renée) lives in Central City in the ‘Flash’ finale. Getting to know her. There's going to be a lot happening leading up to the crossover, which is serving as a [quasi] pilot for ‘Legends.’”

Watch the “Legends of Tomorrow” trailer below:

[SPOILER ALERT: Some spoilers for "Legends of Tomorrow" and "Arrow" Season 4 are below.] 

Sara (who is now White Canary) is pretty much the most mysterious character in “Legends of Tomorrow,” mostly because she died at the beginning of “Arrow” Season 3. However, details about the return of Oliver’s ex have been slowly leaking out. Sara will be in the first seven episodes of Season 4, the fifth of which will include a cameo from Constantine (Matt Ryan).

As previously reported, Constantine will join “Arrow” after Sara’s resurrection to help the Team Arrow deal with bringing back someone from the dead. “Unlike Thea, who wasn’t fully dead, the consequences of using the pit on someone as dead as Sara was creates some unforeseen difficulties ... and John Constantine is uniquely suited to help our team deal with those,” executive producer Marc Guggenheim said, TV Insider reports.

Unfortunately, not as many spoilers have surfaced about the other members of “Legends,” who are appearing on their sister shows, so fans will have to tune in to “Flash” Season 2 and “Arrow” Season 4 to find out what happens to Ray (The Atom), Kendra (Hawkgirl), Martin and Ronnie (Firestorm). Like “Flash” and “Arrow,” “Legends of Tomorrow” will likely recap just enough of these prequel stories to draw in new viewers.

There is good news for those feeling overwhelmed by the number of DC Comics shows on the CW. The network is not planning another show in that universe, according to the Los Angeles Times. “There is no intention, at this point, to spin anything else off,” CW President Mark Pedowitz said.

“Arrow” Season 4 premieres Wednesday, Oct. 7, at 8 p.m. EDT. “The Flash” Season 2 premieres Tuesday, Oct. 6, at 8 p.m. EDT. “Legends of Tomorrow” premieres in 2016.