Clouds of Witness by DL Sayers Part V

Peter is dumbfounded. He had not imagined this happening, that they would turn up some evidence that backs up Gerald's story that he was not killing Cathcart on the fateful night. But knowing how dangerously violent Grimethorpe is, he can't imagine that Mrs Grimethorpe will be willing to give his brother an alibi. And since he (Peter) was alone when he found the letter the story of finding the letter may not stand up in court. Shaken, he gets dressed and goes to see the wife. He can see how lovely she is. He is not surprised that his brother was attracted to her. Gerald's wife Helen is a chilly and prudish woman. Peter guesses that this was not his first affair. He finds Mrs Grimethorpe in the dairy and tells her that he knows that on the night of Cathcart's death, Gerald was sharing her bed, in the main bedroom. He says he has found a letter in the window sash which confirms his brother's being there. Mrs Grimethorpe becomes hysterical and says that it's not true. She will deny it and so will Gerald. He can see that she is terrified, and says that if she is willing to cooperate a little, he will do his best to protect her from her husband until she can get a divorce. He reminds her that Grimethorpe is openly brutal to her. She still refuses. Matters seem to be at an impasse, so he leaves the farm and he and Bunter return to talk to Parker. Parker feels that since the whole business proves that Gerald is innocent, they must use the letter to prove it in court. Peter is more sympathetic to the unfaithful wife.