Thursday's low-key episode of The Big Bang Theory had two stories that never came together. The main plot was about Penny (Kaley Cuoco) feeling taken for granted by Leonard (Johnny Galecki), and the couple turning to Sheldon (Jim Parsons) to draw up a relationship agreement to keep them on the right path.

But the real action was in the secondary plot, in which Howard (Simon Helberg) and Raj (Kunal Nayyar) tried to solve the problem of a squeaky floor in the baby's room. They came up with a very complicated, scientifically sound grid system that isolated the squeaky parts of the floor. It was great in theory — but in practice, avoiding the squeaky spots required feats of acrobatics, feats that Howard was happy to demonstrate, in a bit of physical comedy that was the funniest part of the episode.

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"It's easy once you get the hang of it — step, step, hop onto ottoman."

"Then simply sit, spin, stand."

"Strrrrretch!"

"Then step, grab, tiny pivot and you're there!"

Yeah, Bernadette (Melissa Rauch) isn't going to do any of that. But, good effort.

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

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