Bo returns from L.A. and he shares an emotional reunion with Carly.  She quickly informs him of his brother's mugging.  At the hospital, he and Carly have an awkward encounter with Hope.  Bo questions Roman, but he remembers nothing about his mugging.  Meanwhile, Baker fears Hope's reaction once she learns he went against her orders and framed Arianna.   Arianna is stunned that the evidence points to her as Roman's attacker.  Brady defends his fiancée while Nicole “reluctantly” notes that she doesn't have an alibi.  Arianna is taken down to the station for questioning.  Hope gets the DNA results on the hairs found on Roman - they belong to Arianna.  Hope places her under arrest.    Chloe almost comes clean with Daniel, but decides against it.  She later informs Philip that Nathan knows she had an affair – but doesn't know Philip was involved.  However, a freaked Philip worries that word may still get out.  Daniel learns that Philip told Vivian he and Melanie would have dinner with her.  Furious, Daniel confronts his son-in-law.  Philip, thinking Daniel's talking about his affair, blurts out that he didn't mean for it to happen.   Melanie questions Nathan as to why he has reservations about Chloe.  An uncomfortable Nathan covers, and the two share a nice moment.  Later, Nathan goes to Chloe's apartment and advises she attend sex therapy.  Chloe loses it and orders him to leave - just as Carly arrives.  Has she heard all?   At the hospital, Melanie confronts Stephanie.  She again accuses her of trying to trap Nathan by getting pregnant.  Stephanie denies it.  Melanie demands to see her birth control pills – and when Stephanie refuses, they get into a huge catfight!