Ted pops open some champagne to toast to a great year with his wife, who has just released a new book.
At 8 a.m. on Sunday, ten hours before the wedding in 2013, Ted and Robin finally find Barney passed out in front of his room and are unable to wake him.
Future Ted reveals that Marshall would break that vow when he was running for the New York Supreme Court in 2020 and thought he was about to lose to his old friend Brad (also a judge), only to make a comeback victory.
Robin also joins in Marshall's vow, revealed to be broken a few years later in 2016 while she and Barney are on vacation in Buenos Aires and they wake up in the wrong hotel room with someone else's baby.
Their kiss is successful and Barney awakens long enough to tell the gang that the secret ingredient is actually a lie that he made up to make his friends feel better after the worst episodes of their lives.
The episode ends with Robin talking about how she and Lily actually made out and suggesting that they do it again in front of Ted and Marshall, even though it is clear she wants to do it again for her own pleasure.
Bill Kuchman of Popculturology praised the episode for continuing Barney's evolution, saying, "It's amazing how much effort HIMYM has put into that transition over the past few seasons, but they've really succeeded in transforming a one-dimensional (yet very funny) womanizer into a fleshed-out person.
[2] Max Nicholson of IGN gave the episode 7.5/10, saying it did little to move the story forward, but it did include a few telling flash-forward sequences.