catch in the act

catch (one) in the act

To see, and perhaps apprehend, someone as they are doing something (often something nefarious). The police caught the robbers in the act of ransacking another house. I suspected that my friend was stealing money from me, and then I caught her in the act.
See also: act, catch
Farlex Dictionary of Idioms.

catch someone in the act (of doing something)

to discover someone doing a [bad] deed at the very moment when the deed is being done. I caught her in the act of stealing the coat. He was caught in the act of taking money from the cash box.
See also: act, catch
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.

catch in the act

see under catch red-handed.
See also: act, catch
The American Heritage® Dictionary of Idioms by Christine Ammer.
See also:
  • catch (one) in the act
  • catch somebody in the act
  • caught in the act
  • in the act
  • catch something
  • catch
  • catch (one) (doing something)
  • catch it
  • catch (one) in the act of (doing something)
  • in the act of (doing something)