There is a suspected serial killer in Phoenix, Arizona. At least nine people have been shot in the last four months, and seven have died. Carter Evans is following the manhunt. Source

Dozens of people with blank stares were seen stumbling around a Brooklyn neighborhood on Tuesday. It was a bizarre reaction to an illegal synthetic drug called K2, which is now available all across the country. Michelle Miller reports. Source

Theresa May is officially the new Prime Minister of Britain. David Cameron tendered his resignation Wednesday, clearing the way for May to become the country’s first female PM since Margaret Thatcher. Mark Phillips has more. Source

Police said Sunday evening that a person of interest is in custody. Source

Federal regulators are urging Peloton customers with children and pets to stop using the Peloton Tread+ exercise machine. The Consumer Product Safety Commission says it is aware of 39 incidents with that model, including one child’s death. In a statement, Peloton calls the warning “inaccurate and misleading.” The company says the Tread+ is safe if the “warnings and safety instructions are followed.” Source

America’s theater chains hope summer blockbusters will give business a jolt. Attendance has dropped 16 percent since 2002. MoviePass CEO Mitch Lowe, who was part of the founding team at Netflix, joins “CBS This Morning” to discuss why his company is offering an unlimited monthly subscription to catch theater showings. Source

Despite a court ruling and several headlines early Tuesday that claimed sharing Netflix passwords would now be a crime, the punishment is not so severe. CNET senior editor Dan Ackerman joins CBSN with more. Source

Viggo Mortensen, best-known for his role as Aragorn in “The Lord of the Rings” trilogy, is out with a new movie, “Captain Fantastic.” It may look like an action flick, but he’s not your typical superhero. Mortensen joins “CBS This Morning” to discuss his latest project. Source

The Dallas police chief has defended his decision to use a robot to kill the Dallas shooter. But the unprecedented action by a domestic police department has raised some concerns that such an action could become more common. As Kris Van Cleave reports, supporters say the devices are not “killer robots,” but life savers. Source

Republicans began gathering in Cleveland on Monday to discuss the party platform before next week’s convention. The delegates took up issues like same sex marriage, trade, abortion, and transgender bathroom use — issues presumptive nominee Donald Trump has at times gone against the grain of GOP orthodoxy. Julianna Goldman has more. Source