NX-01 experiences phantom readings leading to a phantom plot involving dense concentrations of dark matter and spreading effective charges of metrion particles. No time for joy at the discovery though - from Admiral Forrest comes bad news: "AG" has died and we've got to wrap up his life in under sixty minutes! (What is it with all the bad messages recently? Mayweather's Dad, Charles the cogenitor, now a Starfleet pioneer splatted on Mount McKinley. Geez can't wait for a cheery season finale.)
Down in the pod bay Archer wants to be alone but T'Pol goes Saavik about regulations, forcing her presence on him like she's in heat or something. They launch and do all the right buttons for the right special lighting effect late in the show of course. During dull moments he tells the tale - to amuse his first officer, no? - of early starship milestones (light-year-stones?) and of the late AG Robinson, first human to travel Warp 2 and destroy a starship in so doing.
After Robinson wraps the NX-alpha around the moons of Jupiter Commodore Forrest threatens to stop the NX program, but Tucker manages an intermix fix. While assisting his superior officers to steal Starfleet property Trip extracts a promise from Archer to "sign him up in a second" should Jonny ever get a ship of his own. Robinson swaps seats with Archer - good thing even artificial gravity has been put on these prototypes - and the second test flight hits Warp 2.5 and proves humans risking reckless sacrifice sometimes actually do get somewhere.
Scenes inside the Starfleet saloon were enhanced with the appearance of famed barmaid Ruby; easy to see why so many male personnel are impressed! (And who is Caroline? Though we can guess why she moved.) We see how young Lieutenant Tucker and Archer first meet, throwing a brewski back just in time for Robinson to verbally attack Archer's father (in a briskly breath-taking moment). Forced to defend his family's honor Archer promptly takes a beating, recalling fond memories of our captain from Season 1.
Despite shuttle-threatening surges this kind of storytelling fails to energize the drama and the story suffers. What makes up for that is the absolutely gorgeous NX-prototypes as well as Levar Burton's craft-driven direction of his cast. It's hard to try and like a new character you know right off is gonna die, but Enterprise has consistently attracted talent and Keith Carradine pulls "Right Stuff" Robinson together. Nice that there's a nebula named for him out there that you can't see.