This is my main question too...how did Nolan end up arrested? I was kind of thinking that Emily threw him under the bus when she was at Victoria's and she saw on the news that Aidan was arrested. Maybe she made some sort of call/sent info that would lead authorities away from Aidan and to Nolan (if only temporarily). OR was Victoria behind it, since she was going to give Nolecorp back to him (supposedly) and needed HIM to find her son but once the info was found she didn't need him anymore.
I wonder if the person who showed up at the door last night was her son, who was ALSO the same person that showed up as the assassin to kill Jack. Wasn't his name Patrick Greggor or something like that? I wonder if Conrad knew about him all along and he's been working for him under the table.