First Look: Sheldon Has A Eureka Moment On The Big Bang Theory

Sheldon and Leonard work through a math problem

Sheldon and Leonard work through a math problem

Sheldon has a revelation when he realizes why a song gets stuck in his head. Plus, Howard and Raj become obsessed with a fan of their band Footprints On The Moon, while Amy invites Dave (Stephen Merchant) over for dinner despite their previously awkward date on the episode entitled "The Earworm Reverberation."
Sheldon makes an important call

Sheldon makes an important call

"The Earworm Reverberation" (Season 9, Episode 10)
Sheldon discusses a problem with Penny

Sheldon discusses a problem with Penny

"The Earworm Reverberation" (Season 9, Episode 10)
Bernadette and Amy chat over coffee

Bernadette and Amy chat over coffee

"The Earworm Reverberation" (Season 9, Episode 10)
Penny and Leonard argue over Sheldon in bed

Penny and Leonard argue over Sheldon in bed

"The Earworm Reverberation" (Season 9, Episode 10)
Howard and Raj become fans of their fan

Howard and Raj become fans of their fan

"The Earworm Reverberation" (Season 9, Episode 10)
Amy goes on a second date with Dave

Amy goes on a second date with Dave

"The Earworm Reverberation" (Season 9, Episode 10)
Sheldon confides in Penny and Leonard

Sheldon confides in Penny and Leonard

"The Earworm Reverberation" (Season 9, Episode 10)
Leonard is stumped by a science problem

Leonard is stumped by a science problem

"The Earworm Reverberation" (Season 9, Episode 10)
Sheldon stops everything when he has a game-changing revelation

Sheldon stops everything when he has a game-changing revelation

"The Earworm Reverberation" (Season 9, Episode 10)
Penny and Leonard share a sweet moment together on the couch

Penny and Leonard share a sweet moment together on the couch

"The Earworm Reverberation" (Season 9, Episode 10)

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