The Big Bang Theory finale was the "perfect love letter" to the show

After twelve seasons, Emmy and Golden Globe-winning sitcom series The Big Bang Theory came to an end in the US on Thursday night, and fans are lauding the two-part finale as the "perfect" farewell to the geeky gang.

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*Warning: spoilers for The Big Bang Theory series 12 finale follow*

Sheldon and Amy (or "Shamy", played by Jim Parsons and Mayim Bialik) received the Nobel Prize, but both struggled with the sudden international spotlight ahead of the awards ceremony in Sweden.

Meanwhile, Penny (Kaley Cuoco) and Leonard (Johnny Galecki) revealed they were pregnant — and, biggest surprise of all, the elevator was fixed (it only took 12 years...)

Sheldon's obnoxious attitude following his win threatened to alienate the rest of the crew, but, in the end, pep-talks from Penny and Amy made him see sense, and he paid tribute to his friends, asking them to stand up in the auditorium during a tear-jerker of an acceptance speech.

"I was under the misapprehension that my accomplishments were mine alone," he said.

"Nothing could be further from the truth. I have been encouraged, sustained, inspired and tolerated not only by my wife, but by the greatest group of friends anyone has ever had."

Fans shared their emotional reactions to the episode on Twitter, dubbing it the "perfect way for a show to end".

"The best finale ever #BigBangTheory hands down. Goodbye to a great show," one fan wrote on Twitter.

"Since this is my private echo chamber, I will admit that I just cried at Sheldon's Nobel peace prize acceptance speech," Linda Neff posted on Twitter.