In the second episode of Season 9, " The Separation Oscillation ," the aftermath of Leonard and Penny’s elopement and Sheldon and Amy’s breakup takes center stage. Leonard and Penny’s Conflict
To put Penny's mind at ease, Leonard visits Mandy (played by Melissa Tang ) at Caltech. [S9E2] The Separation Oscillation
The episode begins with Leonard having a nightmare where he kisses Sheldon to "restore balance" to his marriage after admitting he kissed another woman, Mandy Chow. In the second episode of Season 9, "
Dealing with the breakup, Sheldon attempts to hurt Amy through his web series, "Fun with Flags". The Big Bang Theory recap: The Separation Oscillation " The Separation Oscillation