“Twin Peaks” was ostensibly a show about an eccentric FBI agent struggling to solve the murder of high school girl in the Pacific Northwest, but true fans know it was actually about coffee -- damn good cups of coffee.

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In a new promo for Showtime's airing of back-to-back episodes of the original "Twin Peaks," leading up to the drama's May 21 return, drills down to the matter at hand, providing a supercut of nearly every time someone asked for, mentioned or complimented a cup of coffee. The back-to-back episodes will air on Sho 2 every Sunday, starting at 7 p.m. ET/PT.

Originally airing from 1990 to 1991 on ABC, “Twin Peaks” followed the investigation of FBI Special Agent Dale Cooper (Kyle MacLachlan) into the murder of homecoming queen Laura Palmer (Sheryl Lee) in quirky Twin Peaks, Washington. One of the recurring gags is Cooper’s passion for coffee and his oft-repeated compliment, “Damn good cup of coffee.”

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Showtime will revive the series for a limited run by written by creators Mark Frost and David Lynch, and directed entirely by Lynch. The new season boasts 217 cast members, from series veterans like MacLachlan, Sherilyn Fenn, Michael Horse, Sheryl Lee, Ray Wise, Madchen Amick, Miguel Ferrer, David Duchovny and Lynch himself, to such newcomers as Michael Cera, Richard Chamberlain, Laura Dern, Meg Foster, Ernie Hudson, Caleb Landry Jones, Ashley Judd, Jane Levy, Trent Reznor, Tim Roth, Amanda Seyfried, Eddie Vedder and Naomi Watts.

“Twin Peaks” returns Sunday, May 21, at 9 p.m. ET/PT with a two-hour premiere.