Yesterday,ArrowandThe Flashexecutive producerMarc Guggenheimrevealed the first photo from the highly-anticipatedcrossover eventfor both shows, which will take place in just three weeks. Today, a new poster has surfaced, courtesy ofComic Book Movie, which promotes a fan screening of the two-episode event entitledLegends of Yesterday. The poster features Arrow starStephen Amellfighting alongside The Flash starGrant Gustin, with the new tagline “Heroes Join Forces.” The fan screening is being held by AT&T, with more information to come later on where and when this event will take place.

You may recall that last season’s crossover event pitted these two heroes against each other, but that will not be the case this year.Stephen Amellrecently revealed that bothFlashandArrowwill be fighting a common enemy together, who is believed to beCasper Crump’s Vandal Savage, one of the villainous characters from The CW’s upcoming spinoffDC’s Legends of Tomorrow. Since the crossover event is calledLegends of Yesterday, expect both of these episodes to set the table for this spinoff, while bringing characters from Star City and Central City together.

Arrow Flash Crossover Poster

Yesterday’s photo featuredArrow’s Oliver Queen (Stephen Amell), Thea Queen (Willa Holland), Laurel Lance (Katie Cassidy) and Diggle (David Ramsey), alongsideThe Flashhimself,Barry Allen(Grant Gustin) andDC’s Legends of Tomorrowstars Hawkman (Falk Hentschel) and Hawkgirl (Ciara Renee). It is also believed that anotherDC’s Legends of Tomorrowstar,Brandon Routh(Atom) will surface in this episode. Ray has been missing and presumed dead ever since the last season ofArrow, and we know he will return forDC’s Legends of Tomorrow.

We have previously seen Ciara Renee’sHawkgirlon theSeason 1finale ofThe Flash, and she surfaced again in last week’s episode,The Darkness and the Light. It isn’t known if we’ll see Hawkgirl between now and the crossover episode, but it’s possible that will be the first time we see her in the full Hawkgirl costume. We’ll have to wait and see if Hawkman surfaces on either show before the two-part episode.

Unfortunately, The CW hasn’t released any official plot details for this event, which kicks off with a new episode ofThe Flashon Tuesday, December 1, followed byArrowon Wednesday, December 2. We’ll keep you posted as soon as we learn more about what is shaping up to be one of the most highly-anticipated events of the new TV season. Are you looking forward to seeing Barry and Oliver fighting side by side against a common enemy? Let us know what you think after checking out this poster.