Because Ted asked him to be his wingman, Barney meets a woman named Quinn who sees through all of his plays. To compensate for the poor night out, Barney insists that he and Ted try their luck on the late-night \"Drunk Train\", the last train out of the city, which is filled with the drunkest, most desperate bridge and tunnel people. The duo runs into difficulty scoring on the train, but they succeed on their third attempt when they find a solution: getting drunk themselves, until Barney reveals that he and Quinn had hooked up that first night. Ted realizes that Barney keeps thinking about Quinn, and tells him that if he feels something for her he should go after her, as it is Valentine's Day and such opportunities are rare. Ted admits that he is disappointed that he still has no-one he cannot stop thinking about. At the end of the night, Barney takes a cab ride with a woman but stops himself short of having sex with her. When she asks if he has a girlfriend, he replies that maybe someday he will.
The episode begins with the gang sitting at the bar and Lily showing off her unborn child's \"kicking abilities.\" Marshall and Lily say that they should get going or they will end up having to ride the \"Drunk Train\", the last train to Long Island with all the drunk people on it. (Later, Barney and Ted would ride this train). Marshall and Lily take Robin and Kevin to Vermont for Valentine's Day and they mention that a secret for a healthy relationship is to listen the other person's opinion, and never to keep score (which they actually do).
Meanwhile, Barney and Ted revisit their previous night at a club in which Ted's date with Randi went badly but Barney ended up secretly connecting with Quinn. Barney and Ted ride the Drunk Train two days in a row, but fail to hook up with anyone. On the third night, they get drunk, and two drunk girls ask them to come with them, but Barney passes. Ted then realizes that Barney likes Quinn, who he's been complaining about the entire time. Barney reveals to Ted that he and Quinn slept together at his apartment. Ted tells Barney that he is on the Drunk Train because he has no one he can't stop thinking about, but Barney does and he is wasting his time on the train. Barney denies that he has feelings for Quinn, and takes one of the drunk girls home, but he tells her he can't do this and when she asks if he has a girlfriend, he tells her that maybe sometime he will.
At Ezra's apartment, Ezra comments that Aria seemed to be having nightmares, but she corrects that she was probably just restless. Ezra then surprises her with ballroom dance lessons for their wedding. Aria tells him that she can't commit, before she receives a message from Spencer telling her to come to Alison's house because she messed up. The Liars gather at Alison's house and Spencer tells them how she messed up. Hanna lectures her, Emily tries to ease the amount of pressure Hanna is putting on her, but Hanna angrily questions why Spencer was drunk. Spencer heavily implies that she was drunk because she just found out Caleb cheated on her with Hanna. Hanna realizes and calms down. Emily suggests that if the slip disappears then so does Furey's proof of Spencer's involvement, she offers to go in and take it or destroy it because she knows where the paper work was while she worked at The Radley. Hanna interrupts her saying that she will get the slip. Aria questions what if someone sees Hanna, Alison adds what if Lucas sees Hanna. Hanna tells Alison not to bring him up. Emily informs them all that tomorrow night is the weekly staff meeting, The Radley staff will be \"held hostage in a room and told to smile more\". Spencer states that the security cameras will see Hanna. Hanna tells her they won't. 59ce067264