Franklin & Bash's Mark-Paul Gosselaar will swap his law degree for a criminal record when he plays a notorious serial killer on CSI: Crime Scene Investigation.

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The Las Vegas team will be in for double trouble when Gosselaar takes on the roles of Jared Briscoe and Paul Wintrhop, twins separated at birth, according to Entertainment Weekly. When Bricoe crops up in the premiere, he will be spending his last days in the land of the living on death row, courtesy of D.B. Russell's stellar detective work.

Unfortunately for Russell, a new copycat killer and the discovery of the killer's long lost twin will throw the entire investigation into question.

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It is unknown how long Gosselaar will work with CSI: Las Vegas team, particularly since the CSI Writers' Room recently teased the possibility of a season-long killer for series' fifteenth year.

"Hey, did you guys want to do a season-long killer this year?" the CSI Writers' Room asked in early June.

The CBS drama recently filmed episode 1502 and is just starting on episode 1503. Since the series' is shooting slightly out of order, Gosselaar's premiere episode will not be filmed until after 1503.

Find out more when CSI returns to CBS this fall on Sundays at 10 p.m. ET. Click the video below to see a preview of the season14 finale.