A recent piece of promotional art for Marvel's upcoming Avengers: Infinity War featured Yondu (Michael Rooker) and the Ancient One (Tilda Swinton), possibly hinting at them appearing in the film in some capacity. Now, in an interview with CNET, co-director Joe Russo has revealed that a number of "unexpected characters" will appear in the movie.

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"There's going to be a lot of unexpected characters," Russo said. "There are more surprises packed into this film than any of the others. Part of that is character interactions, new interesting characters, characters that have made small appearances that are really getting fleshed out in this film. A lot of people enjoy the experience, so I don't want to give anything away, but certainly you can expect lots of surprises."

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Debuting in theaters on May 4, 2018, Avengers: Infinity War is a production of Marvel Studios starring Robert Downey Jr., Josh Brolin, Mark Ruffalo, Tom Hiddleston, Chris Evans, Chris Hemsworth, Jeremy Renner, Chris Pratt, Elizabeth Olsen, Sebastian Stan, Benedict Cumberbatch, Paul Bettany, Cobie Smulders, Benedict Wong, Zoe Saldana, Karen Gillan, Vin Diesel, Dave Bautista, Bradley Cooper, Pom Klementieff, Scarlett Johansson, Benicio del Toro, Tom Holland, Anthony Mackie, Chadwick Boseman, Danai Gurira, Paul Rudd, Don Cheadle and Letitia Wright.