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Dane Cook is not laughing about this one.

The comedian opened up about his half brother -- and former manager -- Darryl McCauley, who was arrested in December after being accused of embezzling millions of dollars from Cook.

See photos of stars' mug shots.

"It's a terrible betrayal," he said on Larry King Live Thursday night.

Although McCauley pleaded not guilty to eight counts of larceny over $250, forgery and larceny by continuous scheme, prosecutors allege that the 43-year-old swiped Cook's money while being paid $12,500 per month as his business manager and transferred it into his own bank account.

Check out photos of stars in court.

"I worked with my only half brother for several years," Cook said. "Woke up one day and a lot of stuff was missing. There is a good chunk of money that is certainly not accounted for. That's all I can say about it at this point."

McCauley is currently in jail awaiting a pretrial conference scheduled for April 16.

"But hopefully justice will be served and I can move on with my life," Cook said.

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