Trivia: Hiro's dad's license plate says NCC1701 (the actor playing Dad is "Star Trek's" Lieutenant Sulu), which is the registration number of the USS Enterprise on "Star Trek."
Trivia: When Hiro buys the comic book, he pays with a 1000 yen note, which is a typical price for manga in Japan. This translates into approximately $8.48 American. As a typical 2006 newsstand price for comics is about $2.99, the vendor actually got more than his money's worth.
Trivia: After Hiro and Ando are in Vegas using Hiro's abilities to "cheat" at gambling, they are riding an escalator dressed in identical suits. This is an homage to Rain Man, when Tom Cruise and Dustin Hoffman are in Vegas, also using a special ability to gain the upper hand in gambling, and are also in identical suits on the escalator.
Unexpected - S1-E16
Trivia: Stan Lee appears as a bus driver towards the end of the episode.
Trivia: The date on Hiro's watch, October 2, is the same date this episode first aired in most North American areas.
Seven Minutes to Midnight - S1-E8
Trivia: The title "Seven Minutes to Midnight" refers to the Doomsday Clock that the Bulletin of Atomic Scientists prints to represent the global nuclear threat. The clock was originally started at Seven Minutes to Midnight when it was introduced during the Cold War and it was also Seven Minutes to Midnight when this episode of Heroes aired.
Trivia: In episode 18, "Parasite", Hiro finds the sword listed on the computer with the ID "CRM-114". This tag crops up in many Stanley Kubrick films, including A Clockwork Orange (as "serum 114") starring Malcolm McDowell, who also features in this episode.
Trivia: On the floor of Isaac's loft, the painting of the New York explosion was originally done in black and white. The pilot episode and a couple others were shot with the black and white floor. The color was added in post-production. After a couple of episodes of them having to digitally add color, and realizing they would be shooting in Isaac's loft a lot, the producers finally decided to have the floor painted to save time and production costs.
Chosen answer: Because he's an idiot. From the story point of view, they needed the vault to actually be physically open so that the release of the virus would be a credible threat. Unfortunately, this required that Peter conveniently forget that he could simply walk through The Wall and use his telekinesis to tear the door open instead. Peter's increasingly large arsenal of abilities, where he ended up having pretty much any ability required for any situation, led to a situation where it became necessary to either have Peter apparently forget that he had a given power, as with the vault door scene, or become naively trusting, as with his refusal to scan Adam's mind to confirm his good intent. This problem, which simply made Peter look increasingly dumb as the show progressed, may well have been a key factor in the decision to severely reduce his ability during season three.
Tailkinker ★