Allegro

 is a fictional henchman featured on the original Batman live-action television series. Played by actor Mike Mazurki, he appeared in the third episode of season three titled, "The Wail of the Siren".

Biography
was a henchman who worked for Lorelei Circe, aka the Siren. He was partnered with another man named Andante. The two men were impatient when it came to facilitating the Siren's scheme of swindling millionaire Bruce Wayne out of his fortune. When Siren took mental control of Bruce Wayne, his junior partners, Robin and Batgirl, came to rescue him. Andante and Allegro fought against the sidekicks on the roof of a hotel that Siren had been residing at.