‘The Flash’: Oliver & Barry Reunite — What Brings Back Multiple Heroes? (PHOTOS)

The Flash, as it nears its series finale, is bringing back quite the list of guest stars for its ninth episode, “It’s My Party and I’ll Die If I Want To,” airing April 26. And not only do we have a promo, but The CW has also released photos offering a look at those major returns.

In the episode, Team Flash throws a surprise birthday party for Barry (Grant Gustin) but things go terribly awry when Ramsey Rosso (Sendhil Ramamurthy) crashes the festivities. As the trailer, which you can watch above, shows, Diggle (Arrow‘s David Ramsey) has a gift for Barry that Oliver (Arrow‘s Stephen Amell) would have wanted him to have — but then it appears that everyone is drugged.

And so when the speedster wakes to Oliver, his friend just has one question: “Barry, Barry, Barry, what have you done this time?” Barry then hugs his friend … until Oliver has to remind him to let go. He also has a warning for Barry: It’s not just his world in danger. There’s a new multiverse, too.

“I really wanted to pay homage to Arrow and the characters that Stephen and David played and those are some of my favorite moments in the episode,” series star Danielle Panabaker, who directed the episode, previously told TV Insider.

“Truly when The Flash started, they always had this idea that a Flash episode would include heart, humor, and spectacle. And to me, Episode 9 is an excellent example of that because there’s heart in unexpected places and surprising reunions, and there’s a lot of humor,” she added. “I think part of the success of the crossovers and this Arrowverse has been the chemistry with some of the actors, Grant and Stephen included, and their chemistry together on screen is delightful.”

The photos offer a look at Amell, Ramsey, Keiynan Lonsdale (Wally), and Ramamurthy’s return. Scroll down to check them out.

The Flash, Wednesdays, 8/7c, The CW