Who's the Killer?

Is one of these players Stuart's killer in the Murder Mystery?
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Gang Gathers Around the Body

The gang gathers around Stuart's body during the Murder Mystery party.
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Stuart Dies in the Murder Mystery Game

The gang finds Stuart dead in the middle of the room and must solve his murder.
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Raj Hosts a Murder Mystery Party

Raj talks to his friends about the Murder Mystery Party.
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Howard Smiles at the Bar with Sheldon

Howard has a good time hanging out with Sheldon at the bar.
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Sheldon and Howard at the Bar

Sheldon and Howard hang out at the bar in Houston.
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Sheldon Faces Off with His Mother

Sheldon has a difficult time with the news that she shares with him.
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Mrs. Cooper Talks to Her Son

Sheldon's mother talks to her son while he visits her in Houston.
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Howard and Sheldon Hang Out

While in Houston, Howard and Sheldon hang out together.
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Howard Tries to Comfort Sheldon

Howard helps Sheldon accept the new reality at his home.
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Sheldon Visits His Mother

Sheldon visits his mother while he's in Houston. He's forced to accept new circumstances.
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A Killer Party

Raj's murder mystery game isn't quite the killer party he's hoped for on The Big Bang Theory.
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The Big Bang Theory Season 7 Episode 18 Quotes

Well, I told Howie if I wasn't busy I'd spend the night at his mom's. So for God's sake think of something.

Bernadette

He has a very sensitive butt. Well, it's true. I once saw him sit on a bunch of loose change and add it all up.

Leonard