Tonight's all new episode of hit ABC show "Castle" will return to an era long forgotten, the 1970's. For spoilers about tonight's episode from the actress who plays Beckett, read on.

Stana Katic plays Beckett on "Castle" and the actress recently sat down form an interview with TV Guide to explain the show's trip to the past.

"A key witness in the investigation is stuck mentally in the '70s so in order to find out vital information, we have to reenact the era," the actress explains.

And as to be expected not everyone is on board with the transformation.

"Naturally, Beckett's not into the idea at first. But Castle is all about it," she said.

Katic said that the whole experience was a bit strange. Which is to be expected when an entire police department transports themeselves to another decade just to get information from a wittness.

She explained to TV Guide, "I didn't recognize a few of my costars!"

She went on to say that the 1970's costuming of Detecitve Esposito and Detective Ryan was particularly odd.

"Those guys look like they're doing their own Hall and Oates special!" Katic told TV Guide.

Tune into ABC tonight at 10/9c to catch the blast from the past episode of "Castle."