One of the first questions chef Travis Petersen asks guests as they arrive to his supper club at a semi-secret Vancouver location is how they would gauge their cannabis tolerance. The 34-year-old former "MasterChef Canada" contestant will then dose the forthcoming multi-course dinner with the appropriate amount of cannabis-infused oil.

Eight diners sat around a large wooden table adorned with fall-themed centrepieces and joked about whether they're a one or 17 on a scale of 10 before falling silent as artfully plated dishes of geoduck, octopus and chorizo tacos, and butternut squash tortellini appeared before them -- which Petersen had topped off with an eye dropper of cannabis oil.

Scientists are hustling on behalf of the marijuana industry to find new ways to produce the most valuable compounds in marijuana, ditching greenhouses in favor of big steel vats of yeast that can "brew" cannabis like Budweiser brews beer.

The science, once it hits the market, would be a gold mine for those who perfect it, giving two separate industries -- pharmaceutical and legal cannabis -- stable, potent and cheap sources of the ingredients they need.

 In 72 hours it will be legal for adults in Canada to purchase, possess, or grow recreational cannabis, with some considerable caveats depending on which part of the country you live in.

On Wednesday, Oct. 17 the country will mark a historic moment: the end of the criminal prohibition on marijuana.

It also begins the 12-month march to edibles joining the list of permissible pot products -- the regulations for which Blair said are already in the works.

With the countdown to legal cannabis now measurable in hours, many retailers, police forces, and the general public are still curious and uncertain about how the rollout will go.

A battle is brewing over how Premier Doug Ford's government will divvy up the private sector's share of Ontario's retail cannabis market.

Legislation that would allow companies to operate pot shops in Canada's largest province is now under scrutiny at Queen's Park and businesses are trying to influence key details of the bill. 

Once crucial aspect of the retail regime that's still to be decided: how many cannabis retail licences any one corporation can hold. Government officials say there will be a limit, but that limit has not yet been set. 

It's no secret that Canopy Growth (NYSE:CGC) and other Canadian marijuana growers would love to expand into the huge U.S. market. But marijuana remains illegal at the federal level in the U.S. As long as this remains the case, Canopy and its peers won't be able to directly enter the U.S.

Canada's new law legalizing recreational cannabis goes into force on Wednesday. Here are five things about what's legal and what's not under this historic piece of legislation:

1. Can't vote, can't toke: The legal age for consuming cannabis is at least 18 or 19, depending on the province. The Justice Department says the age restrictions are in keeping with, "a strict legal framework for controlling the production, distribution, sale and possession of pot." Of the three priorities the department cites for accomplishing those goals, the top one is keeping cannabis "out of the hands of youth."

Many investors are taking a close look at marijuana stocks for the first time, given their big gains in recent months. Even though the cannabis industry has been gaining momentum gradually over the past several years, key events like the imminent legalization of recreational marijuana products in Canada have drawn attention to new facets of the market that most investors largely ignored previously.

The world's major alcohol producers can no longer ignore the pot phenomenon, as young consumers may increasingly swap beer and cocktails for joints and cannabis-infused drinks.

Some have decisively seized the moment. Constellation Brands, maker of Corona beer and Svedka vodka, has poured $4 billion into the Canadian marijuana firm Canopy Growth.

The coming market is "potentially one of the most significant global growth opportunities of the next decade," said Constellation Chief Executive Robert Sands. Sales of legal marijuana and related products should reach $200 billion within 15 years and the market is opening "much more rapidly than originally anticipated," he said.

Every now and then, a stock captures the attention of not just investors but the general public, too.

That's been the case recently for Tilray (NASDAQ:TLRY). 

The Canadian marijuana grower listed on the Nasdaq stock exchange in July. Since then, Tilray's share price has skyrocketed to well over six times its opening-day level.

At one point, Tilray was up a whopping 856% -- in just two months of trading. That kind of performance understandably attracted an enormous amount of attention. Now there's another marijuana stock that is beginning to turn heads. Could Pyxus International (NYSE:PYX) be the next Tilray?

Canada is legalizing adult use of marijuana on Oct. 17 and will be the second and largest country to do so.

The federal government established the broad outline of the legalization law but left it up to provinces and territories to fill in some of the details – such as whether to allow home grows, to establish a legal purchase age of 18 or 19, and whether to sell through government-run pot shops or private outlets.

Here’s a look at how the industry will look, as well as some key differences between Canada’s approach and that of the nine U.S. states that have legalized so-called recreational marijuana: