• Stellantis CEO Carlos Tavares is out.
• GE Vernova has a plan to capitalize on surging electricity demand.
• The Thanksgiving box office hauled in an estimated $420 million over the 5-day period.

Here are five key things investors need to know to start the trading day:

1. Beginning of the end

Stock futures were slightly lower Monday as they look to begin the final month of the year. S&P 500 futures and Nasdaq 100 futures each declined about 0.14%, while futures tied to the Dow Jones Industrial Average were basically unchanged. So far on the year, the S&P is up 26%, the Nasdaq Composite is up 28%, and the Dow is up 19%. Follow live market updates.

2. Exit ramp

Stellantis CEO Carlos Tavares is out. The executive resigned on Sunday from the troubled automaker amid "different views" between Tavares and the board, the company said. Stellantis has struggled this past year, particularly in its U.S. market, weighed down by a lack of investment in new or updated products as well as historically high prices and extreme cost-cutting. An interim executive committee will step in while Stellantis conducts a search for its next CEO.

3. Around the clock

There may soon be a (nearly) around-the-clock stock exchange. The 24X National Exchange is set to launch next year and wants to be open for business from 4:00 a.m. ET to 7:00 p.m. ET on weekdays, with the potential to expand its trading window to 8:00 p.m. ET on Sunday through 7:00 p.m. ET on Friday, with a one-hour pause each day, the exchange said last week. The ultra-long trading window would require clearing certain hurdles with the U.S. Securities and Exchange Commission.

4. Nuclear powerhouse

GE Vernova, the spinoff of General Electric's former energy business, has a plan to capitalize on surging electricity demand. The company aims to deploy small nuclear reactors across the developed world over the next decade with a goal to reduce the cost of building new nuclear plants and a target of more than $2 billion in annual revenue from the business by the mid-2030s. "Affordability has been the real challenge for nuclear through the many years," said Nicole Holmes, chief commercial officer at GE Vernova's nuclear unit GE Hitachi. "We're beginning to crack that at this point." Read more about GE Verona's plans from CNBC's Spencer Kimball.

5. Thanksgiving feast

The Thanksgiving box office gobbled up records this year, hauling in an estimated $420 million over the 5-day period. That's the best result for the holiday window in cinematic history, and it's all thanks to the trifecta of "Moana 2," "Wicked" and "Gladiator II." The Disney animated feature brought in more than double its projected tally during its debut window, and "Wicked" continued its impressive early start, becoming the highest-grossing Broadway adaptation of all time at the domestic box office.

– CNBC's Alex Harring, Michael Wayland, Jesse Pound, Spencer Kimball and Sarah Whitten contributed to this report.