For veteran actor Bill Nighy, the idea of doing film sequels is tricky. “We all know how they usually go,” said Nighy the other day, calling from London to talk about “The Second Best Exotic Marigold Hotel” (opening Friday).

“And, by that I mean — going straight downhill! So rarely are sequels anything more than an attempt to squeeze more money out of a successful original film.”

That’s why, after “The Best Exotic Marigold Hotel” became such an international hit, Nighy, the rest of the cast and director John Madden “were very wary about doing a sequel.” However, much to Nighy’s relief, “when the script arrived for [‘The Second Best Exotic Marigold Hotel’], I was absolutely delighted,” he said. “I was completely reassured. Plus, I think they did a brilliant job of extending the story onward from the first movie. I think it’s a perfect continuum.”

Much more challenging was scheduling the entire original cast — Nighy, plus Judi Dench, Maggie Smith, Dev Patel, Penelope Wilton, Celia Imrie and the rest — and finding them available to film the sequel. “That was indeed a miracle,” said Nighy. “Plus we also got Richard Gere this time. He’s an old India hand, so he fit right in.”

The actor was happy to have fun, new things to “chew on” as an actor in the second “Marigold” movie. His Douglas character is showcased as “pretty much the worst tour guide in India,” leading around English tourists while an Indian schoolboy talks to him through an earpiece — reading guidebook information. “That whole idea was really hilarious. When I first read it in the script, I simply laughed out loud,” said Nighy, again chuckling at the thought.

Another twist in the new film’s script had him being a motorbike repairman. Asked if he was mechanically gifted in real life, Nighy admitted, “I’m famously NOT talented in that department.

“Now, it’s not that I don’t believe people are practical or not practical — or mechanical or not mechanical. I just believe that some people are just too lazy, and I’m one of those people who is too lazy to figure out how to fix things!

“In real life, obviously many years ago, I was brought up with the idea that I was supposed to be a car mechanic, because my dad was a car mechanic. And my older brother was apprenticed as a car mechanic. They both went on to run businesses, but they were originally slated to become mechanics. So I saw it coming and knew that was something I had to avoid.

“I was lucky to keep my fingernails clean. But, in the process, I arranged to learn absolutely nothing about the internal combustion engine. I can turn the key to start the car, and I can tune in the radio, and that’s about it.”

Until they shot the first “Marigold” film, Nighy had never set foot in India. But he was not alone among his castmates.

“With the exception of Maggie Smith, none of the rest of the cast had ever been to India until we made that first movie. The rest of us were just like the people we were playing in the movie, so that made it especially nice. … What was satisfying in going back, we had done all [the] introductory sorts of things and getting to know the country. So this time, we could view it and contemplate India in a calmer way.”

Nighy is still amazed the original film went on to gross more than $100 million worldwide. “Nobody involved with the film had any idea that it would become such a huge success,” he said. The actor credited it to both tapping into an older audience hungry for a movie to which they could relate, plus how “India was presented in the first film. It truly did become another character. I really believe that a large part of [why the first film succeeded] was that India looked so marvelous. It’s such an extraordinary place.

“Also, I think people liked the fact the movie showed another version of how to grow old. You don’t just have to fade off into the distance. People loved the idea of characters going to someplace as exotic as India to retire. That is obviously exciting, just in itself.”

While Nighy adored working with Judi Dench — someone he’s acted with many times over the years, both on screen and on the stage — he mentioned that the big Bollywood wedding scene at the end of “The Second Best Exotic Marigold Hotel” was a special treat.

“That final wedding bit was my life for about two weeks of filming,” said Nighy with a laugh. “That was the longest wedding in the history of weddings! But luckily, my character didn’t have to be too much of a dancer, so the pressure was off.”

Asked if he loved to dance in real life, Nighy sighed, “I’m not very good at picking up steps, so I’m dreadful at anything formal, where I have to learn stuff.

“But … I can still throw a few shakes here and there and now and again — just as long as it’s all free form!”