up to one's old tricks

up to (one's) (old) tricks

Doing things that one was known for doing in the past, especially deceitful or mischievous behavior. Food went missing from the school cafeteria? It sounds like Billy is up to his tricks again. I reunited with my two best friends after nearly five years apart, and we were up to our old tricks again in no time.
See also: to, trick, up
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

up to one's old tricks

Behaving in one's usual deceitful or mischievous fashion, as in She's up to her old tricks, telling her parents one thing and her teachers another, or He's up to his old tricks, teasing his sisters until they're in tears. Put as at his old tricks, this idiom was first recorded in 1823.
See also: old, to, trick, up
The American Heritage® Dictionary of Idioms by Christine Ammer. Copyright © 2003, 1997 by The Christine Ammer 1992 Trust. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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