Gintama° - episode 6 - 12 May, 2015

Overall episode #271 Gintoki meets Katsura and Sakamoto at a Joi reunion party, where they attempt to start a past arc in hope of remembering about their former comrade, Kurokono Tasuke. Their attempts to remember always end up going off course, but Takasugi's henchman, Henpeita, drops by and leaves them with a clue about Kurokono. (Source: Wikipedia)