Barney learns something private about Marshall and Lily this week and tears apart their house to find it. Ted and Robin's reunion is put on hold when she has to travel to Russia for work. Ted calls Marshall for advice leaving Lily home alone with a hungover Barney. While Robin is away Ted realizes she is still in love with Barney but Barney tells Ted he is over her. Marshall and Lily's new hobby lands them in hot water with Ted and Barney.