While traveling to observe a black hole in a trinary star system, the captain and crew of the Enterprise are affected by the radiation and become obsessive with trivial issues: Captain Archer with the preface of the biography of his father; Trip with the Captain's chair; Reed with a new security protocol; Hoshi with the galley; Dr. Phlox with Travis' brain. T'pol is not affected and notices the erratic behavior of the crew, and when they faint, she studies a route to save the Enterprise and the crew.
"Singularity" is a simple and tense episode. There is no action, no attacks, indeed anything but the weird behavior of the crew and their preoccupation and obsession with minor situations. In the end, it entertains. My vote is seven.
Title (Brazil): "Singularidade" ("Singularity")