Ensign Boimler records a captain's log for the USS Cerritos' docked day at Douglas Station en route to the Galar system for second contact with the Galardonians. Ensign Mariner catches him and makes fun of his make-believe exercise of being captain.
Mariner's drunk and starts to spar with Boimler with a Klingon bat'leth which severely injures his leg.
Tendi joins the ship at Douglas station and finds Boimler and Mariner for her orientation. Boimler trying to fix a replicator that keeps spitting out hot bananas. Mariner joins them for the orientation tour.
They run into Ensign Rutherford who was recently fitted with a cybernetic enhancement. Unfortunately, it was programmed on Vulcan and keeps trying to tamp down his emotions. He's getting ready for a date that night. Mariner tweaks his implant so he can be nervous.
When Boimler wraps up the tour, Mariner insists they show Tendi the holodeck first. Mariner chooses a beach program. Tendi tries out a temple on Orion. Boimler chooses the ship's warp core.
Boimler's paged to the bridge.
On the planet in the Galar system, Cmdr. Ransom is stung by an insect as he concludes talks with the Galardonian Chancellor.
Boimler arrives at the bridge where Ransom tries to boot him off but Captain Freeman takes Boimler into her ready room and assigns him to spy on Mariner for any infraction of regulations. He and Mariner beam down to Galar to help set up the comms array.
Rutherford and Barnes are having their date in the ship's bar when Ransom's infection turns him into a black bile-spewing, cannibal zombie. He quickly infects others and the bar breaks into a battle. Rutherford and Barnes continue their date conversation while fighting off infected crewmembers.
On the planet, Boimler sees Mariner leave the site with a container of supplies.
Tendi reports to sickbay where all the infected crew members are being restrained and/or treated.
Boimler follows Mariner out and confronts her when she presents her container to some Galardonians. She explains that she's providing farm equipment and while he's distracted, the Galardonians run away, leaving their gate open and a giant spider-like creature emerges and chases them.
While hiding from the spider, Mariner reveals that she was on Galar for first contact and that she has a lot more experience than he does. In trying to wrangle the spider, Boimler ends up being full-body suckled.
Rutherford and Barnes take a spacewalk to get to the rally point, continuing their date discussion. They fight their way into a maintenance hatch where Barnes wants to get romantic but Rutherford is distracted by the fact the hatch doors malfunctioned.
Tendi is learning on the fly, ordered to manually pump Lt. Cmdr. Stevens' heart while he is conscious.
Once the spider falls asleep, Mariner gets Boimler into some borrowed clothes and heads back to the beam-out site. Boimler informs her that he plans to report her for breaking regulations.
Back on board, they find the ship in chaos. T'ana realizes the spider slime Boimler is covered in is the antidote for the infection. Captain Freeman orders a team to get Boimler to sickbay so the slime can be synthesized. A cure is found and administered through the air conduits, saving the ship.
Captain Freeman attributes the success to her senior staff, disregarding Boimler's role in bringing back a cure from the planet. She asks for a report on Mariner and he reports Mariner did everything by the book.
Once Boimler leaves, Freeman puts in a call to the Admiral who refuses to transfer Mariner back to her old ship. Freeman and the Admiral are Mariner's parents.
In the bar, Tendi and Rutherford debrief his date and Tendi empathizes with Rutherford's scientific curiosity over romance.
Boimler lets Mariner know that he didn't report her. Mariner decides she's going to be his new mentor.