Barney convinces himself that Robin has planned a surprise rehearsal dinner at the nearby laser tag place. Lily is distraught when she is not told the details to the rehearsal dinner since nobody thinks she can keep a secret.
This episode provides examples of:
- Cannot Keep a Secret: Lily's famed big mouth is brought up again.
- Jerkass: Invoked Trope. Barney spent the whole episode mocking Robin for being Canadian and wanting to do the reharsal dinner Laser Tag themed. It was just an act and a distraction. Turns out that he staged a big surprise Canada themed dinner for her, because he knew how homesick she was.
- Funny Background Event: As the gang cracks on Canada, they go on so long that a couple at the bar meets, gets engaged, has a baby, celebrates their son's graduation, and one of them dies of old age.