Michael Scofield
In his book "Constructing a Story" and his webseries "Hats Off to the Screenwriters!", Yves Lavandier argues that one can show with dialogue. He takes the example of a scene from "Prison Break" in which pure dialogue between Michael Scofield (Wentworth Miller) and Tweener (Lane Garrison) shows (and does not tell) that Tweener is an expert pickpocket.