When you take a best-selling children's book and turn it into a movie, there is a good chance that its fans are going to have some strong opinions about it.
The first adaptation of Rick Riordan's five-book Percy Jackson series, the 2010 film Percy Jackson & The Olympians: The Lightning Thief, upset some fans because it was not entirely faithful to the novels, more than 20 million copies of which have sold worldwide.
Although it did well enough at the box office (US$226 million or S$290 million) to warrant a sequel - the newly released Percy Jackson: Sea Of Monsters - the new director in charge of the franchise felt more could be done to capture the spirit of the source material.
It helped that 40-year-old Thor Freudenthal, who took over from The Lightning Thief director Chris Columbus, the man behind the first two Harry Potter films, was an avid Riordan reader himself.
"I am always interested in fantasyadventure material, especially when it's grounded in realistic characters who, on the outside, don't look particularly special," he tells Life! at a press event in Beverly Hills recently.
"I flipped through the books and then Chris' film came out, which prompted me to read the rest, so I was a fan even before I did this."
The Berlin-born director was aware that the first film had caught some flak for deviating from the novels, which follow the adventures of Poseidon's half-human son Percy as he discovers his real identity and super-powers. And the books' fanbase is even bigger now because of the success of the first film.
So Freudenthal went into the project wanting to recapture more of the books' humour and lightness of touch.