The Dark Knight and The Fastest Man Alive, the two greatest detectives on any world, unite to explore the mystery behind a certain blood-stained smiley button embedded in the Batcave wall. What starts as a simple investigation turns deadly when the secrets of the button prove irresistible to an unwelcome third party-and it's not who anyone suspects! It's a mystery woven through time, and the ticking clock starts here!
The four-part epic "The Button" begins in Batman #21 and The Flash #21 in April, and continues in Batman #22 and The Flash #22 in May.
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