The episode opens in an abandoned rail yard where a body has been discovered in a car. The victim is Marie Subbarao, her body is strangely distorted and distended like an overstuffed sausage. Lanie the coroner says she suffered from explosive decomposition which occurs in zero atmospheres like outer space.

Castle pulls out a book titled Taken by the Fourth Kind, and starts to whistle the X-files theme. Then faster than a ship in warp drive he starts to spin a theory involving alien abduction and poor Marie getting ejected out a space ship air lock.

Marie was an astrophysicist working at a science center researching radio signals from stars using a radio telescope. But her coworkers say she had been acting strangely and Dr. Charles Vaughn mentions she experienced a life changing event. Castle is still thinking alien abduction. Marie worked with an altitude chamber which if used without protection would have all the horrible effects of space without the view. But there is no blood or tissue evidence in the chamber.
So far the team doesn’t have a human suspect.

Then they find out Marie met with Benny Stryker a former colleague and the author of Taken by the Fourth Kind, the book in Marie’s car. Beckett and Castle meet with him at a support group for abductees. He mentions Marie said she had experienced lost time and abduction. Says she had proof of something she discovered. Benny says THEY wanted to stop her before she found the truth and exposed it. “Like that Will Smith movie but a lot less funny.” Castle quips.

While Beckett sticks to aliens being a crazy idea Castle is warming to the thought of a government cover up. They go back to the science center to discover some unidentified government agents removed everything of Marie’s. Ryan and Esposito are tracking down any other altitude chambers or vacuum packers in the area. Marie had visited an observatory before she died and used their telescope to get a visual of the sources of some radio anomalies she had found. Castle gets excited. She must have found something up there she wasn’t supposed to see.

During all the excitement, Alexis arranges for a dinner between Castle and Ashley’s parents.

“I’m not asking you to dye your hair red and call me Mulder, but just think about it.” Castle says to Beckett on their way back from the observatory. Love that line. Suddenly in a very X-Files moment the car dies as do phones and watches. A bright blue-white light engulfs the car. Are Castle and Beckett about to have a close encounter of their own?

Beckett and Castle find themselves in the dark with a spot light while a shadowy figure interrogates them. THEY want what Marie had discovered. Castle tries to guess who THEY are. CIA? FBI? MIB? Shape shifting aliens who only look human? Then they take an injection gun to the two of them and they wake back in the car with blotchy red hickey like marks.

Back at the precinct Beckett and Castle recover and decide they have to find this proof before the Men in Black do. They recall that Marie’s ex boyfriend had told them she returned a bunch of items to him. They discover a blank cd and pop it in a laptop back at the department.

“No way!” Beckett can’t believe what she is seeing. A star filled sky and a glowing flying object on the screen. They meet with the mysterious agent (who looks like Lyle Lovett. Haha) to make an exchange, photos for information. But the agent tells them they are not after the photos but something that goes much deeper and involves Chinese intelligence and enemy operative selling secrets. The enemy agent intercepted classified information when the radio telescope was pointed at a spy satellite and now the agent, possibly Marie, was killed by her Chinese intelligence handler.

But looking a little deeper Beckett and Castle find Marie’s name forged on paperwork for the telescope. Dr. Charles Vaughn is the real spy! She was abducted, not by aliens but by Charles who killed her after learning what she found. But to catch Vaughn they will need the help of their mystery agent man.
So they head to China Town to find Dr.Vaughn and his handler. They split up and search the basements. Castle speaks Mandarin to a couple workers to get them to leave. Where did he learn that Beckett wonders? “From this TV show I used to love.”

And then there is Vaughn about to be put down by his handler right beside a vacuum packer that was used to kill Marie. Both are arrested and taken in. Beckett and the secret agent have a word in confidence and then Castle begs Beckett to know what it was about. She keeps him guessing. Area 51? Roswell? Loch Ness?