HOWEVER, WHATEVER, WHENEVER.
THIS IS NOT A SPOILER FREE BLOG
because that wouldn't be any fun at all

Catching Elephant is a theme by Andy Taylor
We interviewed the heir to Downton, Matthew Crawley. As Lady Mary’s love, he had plenty of motive to stop Vera Bates from spreading her story. Plus, though he claims to be a “quite good” solicitor, he did nothing to keep Mr. Bates out of prison. Did he kill the late Mrs. Bates and set up Mr. Bates to take the fall? Apparently not because we have ruled out Matthew Crawley in the Village with his Bicycle.
I nominate Solicitor Murray as a suspect. He obviously did not prepare the witnesses, he thinks that perhaps bates ran to the cellar for the poison (as you reminded us “RAN” to the cellar) and he talks as if Bates could be guilty. Cora asked if he was staying over when he was coming to the house and Robert says no (that’s the second time it was asked if he was staying as he wasn’t S1E1). I don’t trust him.
Excellent points all!
I nominate Solicitor Murray as a suspect. He obviously did not prepare...thinks that...