From a lavish production in a historic Detroit theater to Andrea Bocelli crooning opera in Italy, two of the world’s top automakers unveiled new car models Wednesday that they hope will win buyers’ hearts.

In Detroit, General Motors took the wraps off one of Chevrolet’s most important models, the Cruze compact. The new one will be longer, lighter and more fuel efficient — getting 40 miles per gallon on the highway.

Cruze is Chevrolet’s best-selling passenger car worldwide, with global sales of 3.5 million across 115 countries since 2008. But this year in the U.S. its sales are down 12% through the first five months from a year earlier.

For summer fun, Chevy also showed the new convertible version of the new Camaro, which also gets lighter.

Across the Atlantic, Fiat Chrysler laid the groundwork for a sedan that it believes will cement the comeback of its Alfa Romeo brand in the U.S. Executives say the new Giulia sedan that was shown in Milan will have the luxury, sportiness and panache to compete against the world’s premium makers.

At present, Alfa has only a modest entry in the U.S., the limited-production 4C sports car.

Whether its Chevrolet trying to win attention with mainstream buyers or Alfa trying to break back into the top tier of luxury, analysts say the auto business — despite booming sales — is tougher than ever.

“Alfa Romeo is entering the luxury segment at a time when it is more competitive and facing more intense pressure than ever,” says IHS Automotive in a note.

Here are details on the three:

•2016 Chevrolet Cruze

Slated to go on sale next spring, the 2016 Cruze will be the fifth redesigned car model Chevrolet is launching in 2015 and early 2016, with the goal of restoring a reputation it enjoyed in the 1950s and 60s.

The car was revealed Wednesday night at the Detroit’s Fillmore Theater, not just for customers in the U.S., but around the world.

“The new Cruze is truly one of Chevrolet’s most global vehicles,” said Alan Batey, president of General Motors North America.

The new one is 2.7 inches longer, with most of the extra space going to provide more rear-seat leg room.

The new version of the popular compact gets about 40 miles per gallon from its 1.4-liter, four-cylinder Ecotec turbo engine.

Cruze will weigh about 250 pounds less than the 2015 model it replaces. This is accomplished through an aluminum engine block in the engine and a new process of steelmaking.

As with most 2016 Chevrolet models, Cruze will offer buyers the option of Android Auto or Apple CarPlay telematic systems that replicate most icons that appear on one’s smartphone.

John Cafaro, executive director of Chevrolet design, kept a common styling theme that began with the Impala, extended through the 2016 Malibu and now to the Cruze.

“The Cruze’s approach to proportion and premium details adds to Chevrolet’s elevation of craftsmanship, content, quality and a fresh interpretation on an identity that is unmistakably Chevrolet,” Cafaro said.

“They’ve been pretty conservative in this segment for some time, but that has served them well in the market,” said Stephanie Brinley, an industry analyst with IHS Automotive. “What it needs to be is fashionable and help Chevrolet get more loyalty and bring new people into the brand.”

Like other compact models that have been introduced in the last year, Cruze will face headwinds of moderately inexpensive gas and many Americans preference for pickup trucks, SUVs and crossovers.

The new Cruze takes several strides forward in safety technology. There are 10 air bags, a side blind zone alert, rear cross traffic alert, lane departure alert and forward collision alert. All sensor-enabled steps down the road to autonomous driving.

On the infotainment front, there will be a 7-inch diagonal screen on which the next iteration of Chevrolet MyLink will be displayed as well as Android Auto. Apple loyalists who want the CarPlay option will be able to get an 8-inch screen.

2016 Chevrolet Camaro convertible

Camaro convertible loses 200 pounds compared to the current version when it goes on sale early next year. But GM officials say it will also have a stiffer body.

An electro-hydraulic power roof system features multilayer construction designed for comfortable, quiet driving in all seasons. The top mimics the sleek silhouette of the Camaro coupe.

The structure enables the top to fold down completely beneath the belt line. The hard cover automatically covers the folded top.

The convertible will come with six engine and transmission combinations, including a 2-liter turbo rated at 275 horsepower, an 3.6-liter V-6 producing 335 horsepower and the LT1 6.2-liter V-8, which is certified at 455 horsepower. There is a six-speed manual or eight-speed automatic transmission.

The car’s leaner, stiffer platform and smaller dimensions are accentuated by a sculpted exterior. Meticulously tuned in a wind tunnel, the exterior contributes to performance through better aerodynamics for better handling while enhancing highway fuel efficiency.

2016 Alfa Romeo Giulia

Alfa Romeo Giulia was revealed today in Milan as the first salvo in an ambitious plan to create a renaissance for the storied brand and climb to the same level of respect given to Audi, BMW and Mercedes-Benz.

The Giulia will have an aluminum, six-cylinder turbo petrol tuned by engineers with Ferrari background that delivers 510 horsepower. The accelerates from 0 to 100 km/h in only 3.9 seconds.

The car has a “perfect” 50/50 distribution across two axles to improve the driving dynamics.

The launch of the Giulia — and the models that will follow — is among the main pillars that will either lead to FCA’s success over the next five years or will lead to its failure.

Today, Fiat Chrysler CEO Sergio Marchionne reaffirmed plans to spend 5 billion euro or $5.6 billion to develop eight new models including the Giulia by 2018 and global sales of 400,000. North America is expected to account for about 150,000 of those sales.

FCA plans to achieve its lofty goals for Alfa Romeo by designing cars that connect with Milan’s roots as a fashion capital and to launch cars that include technical and performance breakthroughs.

Today, Alfa Romeo is viewed in Europe as a brand that aspires to be premium but falls short.

Harald Wester, CEO of Alfa and Maserati, said the new Alfa Romeo models will be designed to regain “respect for the brand, respect for its substance and shape, and its history.”

To get that respect, the automaker intends to make Alfa Romeo cars and crossovers with high-performance engines, distinctive styling and unique technology.

“In our view, the aggressive product roll-out planned at Alfa Romeo can revive the brand and add to the value of the group,” Goldman Sachs analyst Stefan Burgstaller said in a recent report.

Snavey reported from Modena, Italy, and Gardner from Detroit. Both write for the Detroit Free Press. Woodyard reported from Los Angeles.