NEW YORK — The young-adult adaptation “The Maze Runner” from 20th Century Fox topped the box office with $32.5 million, outpacing the $13.1 million debut of Liam Neeson’s private eye thriller “A Walk Among the Tombstones” and the $11.9 million for the ensemble-cast “This Is Where I Leave You,” according to studio estimates Sunday.

The strong opening for “The Maze Runner,” adapted from James Dashner’s science-fiction novel, is a big success for a movie that cost $34 million to make and was released in the normally quiet month of September. Fox aimed to make the film — about a group of teenage boys mysteriously locked inside a giant maze — the first post-summer event movie, putting it on IMAX and large-format screens.

Aronson said attracting young moviegoers has been “the Achilles heel” of Hollywood. But the studio has recently found success with relatively low-budget YA releases, like “The Fault in Our Stars,” the Shailene Woodley melodrama that made $125 million earlier this year despite a budget of just $12 million.

Aronson announced Sunday that the planned sequel, “The Maze Runner: The Scorch Trials,” will open Sept. 18 next year.

1. “The Maze Runner,” $32.5 million ($37.6 million international)

2. “A Walk Among the Tombstones,” $13.1 million ($5 million international)

3. “This Is Where I Leave You,” $11.9 million

4. “No Good Dead,” $10.2 million

5. “Dolphin Tale 2,” $9 million ($1.2 million international)

6. “Guardians of the Galaxy,” $5.2 million ($5.2 million international)

7. “Let’s Be Cops,” $2.7 million ($1.5 million international)

8. “Teenage Mutant Ninja Turtles,” $2.7 million ($7.3 million international)

9. “The Drop,” $2.1 million.

10. “If I Stay,” $1.8 million ($3.2 million international).