The last episode of "The Big Bang Theory" touched upon several sensitive topics, including the end of Sheldon's "Fun With Flags" web series, Bernadette's snarky attitude and the death of Professor Roger Abbot.

In last week's episode, titled "The Champagne Reflection," Sheldon recorded the final installment of "Sheldon Cooper Presents Fun with Flags." Between balancing his full-time career and girlfriend, he decided that he no longer had time to dedicate to the popular Internet show.

"After only 232 episodes," said Amy, before Sheldon jumped in to correct her.

"233 if we include the one that somebody forgot to press record on," Sheldon interrupted.

"You said you weren't going to bring that up," snapped Amy.

"And you said you were going to press record," Sheldon replied.

During the series finale, Sheldon and Amy presented a highlight reel, featuring Amy as a kangaroo, Kripke playing "Flag or Not a Flag" and Sheldon in costume as Betsy Ross.

LeVar Burton was also the special guest in its finale, reports Movie News Guide.

Sheldon then ended the show with an emotional sendoff.

In the meantime, Leonard, Howard and Raj began to reflect upon their personal life achievements after they found a 50-year-old champagne bottle in a dead professor's office. The professor didn't open it because he never achieved anything worthy of the champagne his mother had bought him a half-a-century ago. As a result, the geeky gang pondered how they would feel if they died before completing their bucket list, reports Den of Geek.

Meanwhile, Bernadette dealt with her abrasive attitude, which was beginning to affect her career.

At this time, there is no word on when the next new episode of the show will broadcast.

"The Big Bang Theory" Season 8 airs every Thursday at 8 p.m. EST on CBS.