“Room 104” has been teasing its season finale since the trailers for season three were initially released. The beaming color and vivacious plant life that comprises the season three promotional cover photo on HBO finally blooms to fruition in “The Specimen Collector.” 

The episode opens with Marianne Wallace (Cobie Smulders), a botanist coming back from an expedition, sitting at the table by the window with notebooks strewn about, leaves pressed onto the pages. She is on the phone, telling someone named Joe (Ian Merrigan) that her flight was delayed, but that she sent him “the specimen” in the mail. As her conversation continues, the camera travels across the room and under the bed where her backpack is tucked away. It pushes into an extreme close-up in which a luminous piece of pollen floats off her backpack and into the room’s carpeting. “Room 104” is always quick to the chaos. 

Marianne is woken up slowly to the light tickle of a large banana leaf grazing her arm. She shoots out of bed and is confronted with a once typical hotel room completely transformed into a jungle of jurassic flowers and dripping vines. She walks through the room slapping herself in the face, trying to wake herself up before she realizes that she is not in a dream. Ecstatic, she extends her stay in Room 104 by a week so she can examine the specimen, taking pictures of the foliage and sending them to her colleague. 

After this, Marianne begins to diligently and consumingly document the ecosystem unfolding around her. She is running out of food and water, but doesn’t seem to care. Instead, Marianne strips bark from the trees to eat as she watches ants and beetles crawl through the microscopic jungle. But eventually, Marianne snaps at a maid, slamming the door on her to keep her from coming in — and this is when Marianne’s botanist bliss is disrupted. 

The hotel manager (J.P. Giuliotti) knocks on the door, attempting to enter the room. Marianne begs him to leave her alone, to let her study the world which has been created in Room 104. A call from Joe interrupts their conversation. Joe tells Marianne that the plant and animal species she has been documenting are archaic, extinct species coming back to life in Room 104. Marianne desperately explains this to the manager and tells him that the museum she works for will compensate him greatly if he lets her stay in the room, to which he agrees. 

It is clear that Marianne has become deeply and emotionally involved with the ecosystem thriving in this room. She begins to talk to it calmly and watch it move and grow with awe, unconcerned with the happenings of the outside world. Marianne tells Joe she is afraid that the plant life will not be able to live outside of the room, and that she must protect it from extinction — butt Joe is concerned by the way she talks about the room. Worried that she wants to stay there forever, calls the National Invasive Alien Species Department of Interior, or NIASDI, to come for her. 

Government officials come knocking shortly after Marianne’s phone call with Joe. She refuses to let them in, so they send in a mediator to get her to let them in. The mediator, Dr. Eugene Hill (Aasif Mandvi), comes to the door and offers Marianne a bottle of water as an olive branch. Marianne makes him give her his cellphone and strip down to his boxers before he can come in. 

When he does, Marianne shows him around the room to examine the species there. Eugene tells her that he is there to make sure that the specimens are preserved the way she wants them to be. After Eugene somewhat gets through to her, Marianne calls her husband Andy and says she is sorry she hadn’t called but was excited to have finally found something special. 

When she hangs up the phone, Eugene offers her the water again — but she is suspicious of it. To prove nothing bad is going to happen, Eugene takes a swig from the bottle, and Marianne follows. But of course, they both quickly lose consciousness and NIASDI enters the room. 

The episode ends on a shot of Room 104, returned to its original state, implying that NIASDI destroyed the ecosystem which once flourished there. The door to the room opens and a family dressed in Renaissance faire garb enters to jaunty old-timey music. As the kids play and the parents drop their suitcases, one of the butterflies from Marianne’s ecosystem flies across the room. Her plants might be lost, but the world is not forgotten — and neither is season three of “Room 104.”