Sheldon beta-tests an MIT invention after hearing it can help him read people's emotions. Also, Leonard can't hide his feelings when Penny announces her brother is coming to town and Raj invites his ex-girlfriend over to give him dating advice.
When Franco's creative new donut flavours become bestsellers, Arthur tries to prove he's still relevant by coming up with a unique one of his own. Also, Fawz works to dream up an inventive password in order to keep Maya and James from stealing his WiFi.
When Tim accidentally shaves off a huge chunk of eyebrow before an important photo shoot, he hopes Jen and Colleen's grooming expertise can fix it. Also, when Gigi passes away, Greg makes an anonymous donation with the money she left him.