If you want an idiomatic expression you may use:

[In a nutshell:][1]

You can use in a nutshell to indicate that you are saying something in a very brief way, using few words.

 

• In a nutshell, the owners thought they knew best. This, in a nutshell, is what Richard Chaplin appears to have done.

(Collins Dictionary) [1]: https://www.collinsdictionary.com/dictionary/english/in-a-nutshell

If you want an idiomatic expression you may use:

In a nutshell:

You can use in a nutshell to indicate that you are saying something in a very brief way, using few words.

• In a nutshell, the owners thought they knew best. This, in a nutshell, is what Richard Chaplin appears to have done.

(Collins Dictionary)