With more than 140 attractions in 24 countries, including 10 Legoland theme parks and partnerships with Lego,

Hasbro Inc.

and Sony Pictures Entertainment, Merlin Entertainments is one of the world’s largest theme-park companies, behind only

Walt Disney Co.

in attendance.

Besides its Lego parks, Merlin Entertainments also operates “Peppa Pig” parks based on the Hasbro character and announced a deal with

Sony

earlier this year for rides and attractions based on the “Jumanji” film franchise.

In an interview, Mr. O’Neil said he wants to further pursue partnerships with companies that have intellectual property that is a good match for its parks. “We will be very active in making sure brands know we are open for business,” he said.

Mr. O’Neil, 52 years old, was previously chief executive of Harris Blitzer Sports & Entertainment, whose holdings include the Philadelphia 76ers NBA franchise and the NHL’s New Jersey Devils franchise. He left that position in June 2021.

He also served as president of Madison Square Garden Sports, where he was in charge of the business operations for the NBA’s New York Knicks, the WNBA’s New York Liberty and the NHL’s New York Rangers. Mr. O’Neil said he was drawn to Merlin Entertainments for the same reason sports has held appeal for him, which is to “bring joy and connection” to people and families.

“Scott has significant experience in the entertainment industry, a proven track record of delivering business transformation and the vision and ambition to lead Merlin through the next exciting stages of its global development,” said

Roland Hernandez,

chairman of Merlin Entertainments.

Like Disney, which last week reported record quarterly revenue results at its theme parks, Merlin Entertainments also believes it has turned the corner following the slowdown in attendance in recent years because of the Covid-19 pandemic.

In the company’s half-year review, Merlin Entertainments said Covid restrictions have lessened significantly in many of the regions where it operates. The significant exception is China, where lockdowns continue to keep attractions closed.

Merlin Entertainments is owned by a consortium that includes Kirkbi Invest, the investment arm of Lego parent Kirkbi.

Write to Joe Flint at joe.flint@wsj.com