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We've got to catch those thieves red-handed.
— Kermit the Frog · The Great Muppet Caper

Behind the line May contain spoilers.
Our reading
An editorial interpretation.
The speaker insists that the thieves must be caught in the act, with proof undeniable. 'Red-handed' carries the sense of seizing wrongdoers at the moment of the crime, so the line expresses determined, urgent resolve to gain evidence rather than merely suspect or chase them.
Context reviewed