The wait is finally over - The Walking Dead is back in our lives, with season nine streaming weekly on NOW TV. To celebrate the return of Rick Grimes and the walkers, here are nine numerical nuggets of behind-the-scenes insight, and what we know so far about the new season...

90 minutes

… how long it takes the make-up team to transform a single extra into a walker. Bear in mind that up to 70 extras can be shooting in one day. The show's special effects guru Greg Nicotero told CNN: "They all have contact lenses; they all have custom dentures; some people we like to make more rotted than others." Wondering how they nail that unwashed matted hair look? Loads of conditioner.

BTS The Walking Dead S9pinterest
20th Century Studios

18 months

… have passed since the events of the season eight finale. We knew that there would be a time hop, but it was actor Tom Payne (who plays Jesus) who revealed exactly how long it's been since the defeat of Negan. In a season nine preview special that aired on AMC, he said: "[W]hat's happened now is a year and a half after all that has ended… you are really seeing each community's strengths. Everyone has to go back to basics."

3 dead characters

… will make an appearance in season 9. New showrunner Angela Kang confirmed at New York Comic-Con that Jon Bernthal (Shane), the late Scott Wilson (Hershel) and Sonequa Martin-Green (Sasha) are returning to the series. We're guessing in dream sequences or flashbacks.

5000 to 1

The ratio of walkers to humans, according to the blurb on the comic book series - meaning there are roughly 7 billion walkers in TWD universe. And as a rule they're never referred to as 'zombies' in the show. Instead there's a myriad of nicknames: lurkers, biters, lamebrains, creepers, deadies, empties, stinkers – and skin-bags.

BTS The Walking Dead S9pinterest
20th Century Studios

199 dollars

How much it costs to buy a (non-fatal) replica of Michonne's hand-forged sword from the official AMC shop. Or how about a replica of Lucille's barbed-wire baseball bat instead?

.357

Talking of weapons, Rick uses the same gun in all nine seasons – a .357 Magnum Colt Python.

$3.4 million

The estimated budget per episode of The Walking Dead. In comparison, a Game Of Thrones episode costs roughly $10million to make.

The Walking Dead S9pinterest
20th Century Studios

2am

Extras who play walkers are told to move like they're leaving a bar at 2am to nail that zombie stagger, according to an interview with Nicotero. They're also instructed to stay completely silent – all the creepy noises are actually added in post-production.

400 dollars a month

According to ABC News, this is how much the residents of Senoia, Georgia - where nearly all of TWD is filmed - are paid to compensate them for the hassle of filming interrupting their daily lives, and to incentivise them to not share any spoilers.

Watch FOX's The Walking Dead S9 streaming weekly on NOW TV, plus discover loads more of the latest and best shows