Hulu surprised “Veronica Mars” fans at ComicCon on Friday by releasing the show’s eight-episode fourth season a week early. Such instant gratification hasn’t been the norm for “Marshmallows,” the nickname given to longtime devotees of that Southern California noir. Through three ratings-challenged seasons on UPN and CW beginning in 2004, and one Kickstarter-funded movie in 2014, its creator, Rob Thomas, and his cast have maintained its continuity remarkably well. But the time between installments has made it difficult to keep everything straight.

During its network run, “Veronica Mars” was two shows at once: an ultra hip, modern-day Nancy Drew, full of self-contained mysteries cracked by the prodigious daughter of a private eye, and a sun-scorched procedural in the tradition of “Chinatown” and “The Long Goodbye,” revealing the sordid underbelly of a seaside town. With the movie and the new Hulu season, however, Thomas no longer had to worry about appealing to a more general audience. Season 4 jettisons case-of-the-week episodes to tell one complete story about a series of bombings that turns the city of Neptune into a less-than-ideal spring break destination.

The good news is, it’s possible to dive right into the fourth season cold. But the series does make reference to events dating back to the beginning, so it’s better to know the basics. Here’s where all the relevant players stood heading into the new season:

Veronica (Kristen Bell)

Through her last two years of high school and most of her first in college, sleuthing was a sideline in Veronica’s life, an unofficial extension of her father’s business as a private investigator. Nine years later, in the movie, she shelved an offer from a prestigious New York law firm and returned to Neptune to defend Logan, her on-again-off-again boyfriend, from a murder charge. She ultimately opted to stay home and take over the family business, Mars Investigations, fighting the corruption that roils her town. The two defining cases in her life both happened in the first season: The murder of her best friend, Lilly Kane, which was pinned to her boyfriend’s philandering movie star dad, and her own drugging and rape at a party, which takes longer than a season to solve.