Supergirl‘s role has been revealed in the highly anticipated Arrow Season 5 and other CW superhero series crossover.

According to Arrow executive producer Marc Guggenheim, the technology that brought Barry Allen/The Flash (Grant Gustin) in the alternate universe where Kara Danvers (Melissa Benoist) lives is the same tool Supergirl will use to enter the Arrow world.

“Last year, Supergirl established that The Flash was able to make his way to what I call ‘Earth CBS,’ and it stands to reason that, with the proper breach technology, the reverse can happen. Once the heroes realize that they’re up against aliens, they decide that they need an alien on their side, and fortunately, Barry knows a really nice one,” TheWrap quoted Guggeinheim saying.

Apparently, the crossover will feature a threat that will force Supergirl to travel to Earth.

The CW huge crossover will involve Arrow, The Flash, Supergirl and Legends of Tomorrow.  It will also mark the 100th episode of Arrow. The biggest crossover on television is expected to air in November.

Arrow Season 5 actor Stephen Amell also shared some updates on the crossover among the Berlati-produced series. In his Facebook live streaming, Amell teased the crossover will not be five different shows but five different episodes.

Amell earlier posted photos of what fans could expect in the crossover. He posted several pictures with the characters who will appear in the four-way crossover. In one photo, the Green Arrow was seen standing on the rooftop alongside Supergirl.

Meanwhile, fans are excited for the third episode of Arrow Season 5 which airs on October 19. Villain Prometheus is expected to appear in Episode 3, titled A Matter of Trust.

Guggenheim has also revealed that villains Malcolm Merlyn (John Barrowman) and Damien Darhk (Neal McDonough) will also return this season.

Arrow Season 5 airs every Wednesday at 8/9c on The CW.