Have (someone) by the short hairs British informal verb phrase
"Have" can be replaced by "get".
To have someone in a difficult situation in which you have complete power over them
I had Jay by the short hairs because I knew what he had done.
He had us by the short hairs when he found out about our little secret.
I cannot do anything against him because he has my by the short hairs.
The verb "catch" should be conjugated according to its tense.
To start doing something enthusiastically and energetically
We have a lot of work to do today, so let’s get stuck in.