Mayim Bialik and Simon Helberg

CBS's The Big Bang Theory is mixing things up on its Oct. 3 episode by pairing characters that rarely interact for a big scavenger hunt involving a hidden gold coin.

Raj (Kunal Nayyar) organizes the citywide search, which partners Leonard (Johnny Galecki) with Bernadette (Melissa Rauch), Amy (Mayim Bialik) with Howard (Simon Helberg), and Penny (Kaley Cuoco) with Sheldon (Jim Parsons).

"In six years, I've never had scenes alone with Simon Helberg, and our scenes involve a lot of singing," says Bialik. Amy and Howard duet throughout the episode for a tribute to Neil Diamond's greatest hits after they discover their shared adoration for the musical icon.

And in a future episode, the Amy/ Sheldon dynamic will take another turn when the couple ends up working together at his Cal Tech campus. According to exec producer Chuck Lorre, "Sheldon is not equipped to have his mate being at his workplace and it doesn't go well." Does it ever?

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