The upcoming episode of "The Big Bang Theory" season 10 will see Sheldon (Jim Parsons) upset with Amy (Mayim Bialik) after finding out that she has lied to him.

The synopsis of the seventh episode, titled "The Veracity Elasticity," reveals that Amy will lie to Sheldon about her apartment undergoing some repairs so that they can continue living together. The pair will also host another episode of "Fun with Flags" but, since they are in Penny's apartment, they will do it there instead. 

Meanwhile, Leonard (Johnny Galecki) finds out that Penny (Kaley Cuoco) has been secretly putting his collectibles in storage. As a result, he allows Penny to decorate Sheldon's old room.

A teaser trailer for the new episode has also been released online. The 20-second clip starts out with Sheldon asking Leonard in Klingon, "Is Penny lying?," as the latter looks at his wife suspiciously. "Why are you speaking Klingon?" Amy asks her boyfriend. "Why are you speaking English?" Sheldon hilariously retorts.

The next scene shows Sheldon and Leonard eating in the Caltech cafeteria. Sheldon wonders why Amy would lie to him after everything they've been through — including sharing a Netflix password. The video also teases Sheldon going into a room with red lights as he surprisingly asks, "What is going on?"

Meanwhile, here is a brief recap of the previous episode, titled "The Fetal Kick Catalyst."

Penny discovered that she had fans of her work from "Serial Ape-ist" when she attended a comic convention with Leonard, although it wasn't because of her acting. Leonard found a few fans of his own when the guys at the convention were told that he was married to Penny.

Elsewhere, Sheldon and Amy threw a trial party and invited stand-in guests like Stuart (Kevin Sussman). Meanwhile, Howard (Simon Helberg) and Raj (Kunal Nayyar) bought a minivan in preparation for Bernadette (Melissa Rauch) giving birth.

"The Big Bang Theory" season 10 airs Thursdays at 8/7c on CBS.