The 33-year-old actress took to her Instagram Story on Wednesday to recount an incredibly nice thing that a stranger did for her amid her "emotional" week.
"So I have had the strangest week. It's been very up and down, very emotional to be honest. Probably just coming to the end of the show and, I don't know, lots of other things," she said in the video, referring to the upcoming series finale of CBS' The Big Bang Theoryafter 12 seasons. "But a really sweet thing happened to me a few days ago and I had to share."
Cuoco -- who wore her hair in a top knot, appeared to be without makeup, and opted for a simple white T-shirt -- went on to detail how she left her wallet at Sharky's restaurant in Calabasas, California, and didn't realize it until hours after the fact.
"I became fully hysterical and didn't know where it was and traced my steps and was like, 'Oh my God, I left it there. It's gone. It's gone,'" she recalled. "I was crying. I was so upset. So I called Sharky's and someone had turned it in."
Whomever turned it in was obviously a big fan of Cuoco, as they labeled the wallet "Penny" before handing it over to the manager, referencing her character on the long-running sitcom.
"Whoever did that, whoever is out there, thank you," she emotionally said. "I wish I could've met you. I would've given you all the cash in my wallet or whatever was in there. I really would've given you anything. I was so grateful that there was someone so sweet on this earth, and honest. And it didn't go unnoticed and I will never forget that because that could've been a very bad day for me."
Cuoco concluded her story with tears in her eyes, praising both the kind stranger and the restaurant's manager.
"You guys were so nice," she said of the Sharky's staff. "I came in crying and they were like, 'Penny!' So, there is good in the world."
She captioned each clip in her story with kind words, declaring the stranger "a good soul," expressing her wish that she could thank them in person, and promising that she "will never forget this sweet sweet act of honesty and kindness."
"There are good people in the world," the final clip read.
Prior to sharing the emotional clip, Cuoco took to Instagram to celebrate a major Big Bang Theory milestone.
"@bigbangtheory_cbs is officially the longes- running multi-cam show in history surpassing the great show Cheers," she wrote alongside a group photo of the cast standing in front of cupcakes that spelled out "276," which is the number of episodes made. "? Blessed, humbled, amazed, grateful. Thank you to everyone who has supported us the last 12 years. ? THANK YOU!"
When ET's Nancy O'Dell caught up with the actress back in January, she revealed she is not ready to say goodbye to the series. "I don't wanna leave, I don't wanna leave," she said. "I said it. I don't wanna leave!"
"Everyone’s doing rebooting. We might as well do it in, like, a year!" she quipped.