A flat tire during Leonard's bachelor party weekend in Mexico tests the guys' skills; Penny is compelled to tell her family that she and Leonard eloped.
An impending change to his living arrangements inspire Shelton to revert to 2003, before he met Penny and Leonard; Raj and Howard form a band.
Sheldon's excitement about his Meemaw's visit is soon over as she clashes with Amy. Raj thinks about his relationship with Emily when he meeting somebody new.
Amy and Sheldon decide to host a Valentine's Day edition of Fun With Flags. Penny and Leonard find it hard to deal with the fact that they are getting older.
The gang celebrates Sheldon's birthday for the first time in nine years and they manage to surprise him with a special guest.
A surprise revelation is made by Sheldon after Amy purchases him a new laptop. Leonard and Wolowitz get sold out by Koothrappali.
The group enjoy a get-together but a minor argument between Sheldon and Leonard turns into a heated debate.