"Arena for a Fallen Hero!"
The Falcon's mind has shut down as a result of the Red Skull's conditioning. S.H.I.E.L.D. agent Jeff Cochren's only resort is to use "shock therapy" to snap the 'Snap' out of Sam Wilson's head.
Captain America is ordered to fight his best friend in order for the real Falcon personality to assert itself. Reluctance stays Cap's hand at first, but when images of his greatest foes start to appear in the S.H.I.E.L.D. chamber, Cap has to defend himself from waves of attacks from the villains, not realizing that every blow he strikes shudders the Falcon.
In the midst of the chaos, the Enchantress sidles up to Cap to canoodle with him and make him forget his friend's plight. Falcon regains consciousness, of a sort - but it's the 'Snap' Wilson personality which has emerged.
'Snap' is instantly paranoid, not being aware of any of the last six years he spent as Cap's partner, and cautiously approaches the man in Red, White and Blue. Cap's own altered perception leads him to see Baron Zemo, the man he holds responsible for Bucky's death in World War II. Cap lashes out instinctively, and the Falcon is floored like a rag doll, yet again.
Street-smart 'Snap' Wilson's not taking being treated like some tawdry punch-bag. He bundles Steve over, but is still rebuffed. Falc sets Redwing on Cap, and the Avenger stands his ground, not defending himself, hoping Falc will call his pet off before he gets shredded by the bird's talons.
At the last second, Falc calls Redwing off and makes peace with his fabled mentor. When the whole story about the Red Skull is explained in full, Falc still can't quite believe it, but there's no time to muse over it, as the 'Enchantress' reveals herself to be the presumed dead, Nightshade. It's 'Deadly Nightshade'. The lady is very particular about that.