Who helps with the escape attempt in chapter 54? Explain the results of the escape attempt for Compeyson, for Magwitch, and for Pip?

Pip, Startop and Herbert help in the escape. The steamer crushes Pip's boat, Compeyson and Magwitch disappear under the water, and Pip, Startop and Herbert find themselves in a police boat of sorts. Magwitch finally comes up from the water. He and Compeyson and wrestled for a while, but Magwitch let him go and now Compeyson is presumably drowned. Once again, Magwitch is shackled and arrested.

Pip sits down next to the injured and exhausted Magwitch, and feels that he will stay by Magwitch's side until the end. Pip also realizes that the English government will take all of Magwitch's fortune.