Sequels are the bane of movie critics, who decry the dearth of original ideas, but a boon to movie executives, who might argue that they are giving fans what they want.

Love 'em or hate 'em, there is no escaping 'em. There are about 20 sequels headed to cinemas until the end of the year, ranging from superhero flicks such as X-Men: Apocalypse to animation Finding Dory to horror title The Conjuring 2.

Sequels build on a proven track record and have a ready audience in the form of those who liked the previous movie or movies.

Public relations executive Keith Kay, 29, is a fan of series featuring the superheroes X-Men and The Avengers.

He says: "With sequels, it's about creating a more immersive universe. There's an evolution of the story, especially in comic book movies where nothing is static, and you get to see characters develop in depth over several films."

A Twentieth Century Fox spokesman says: "For the X-Men movies, established characters such as Professor X and Magneto are well known to moviegoers. Picking up from the previous film (X-Men: Days Of Future Past, 2014), there is a sense of anticipation for the upcoming X-Men: Apocalypse in wanting to knowing what happens to these characters."

Last year, seven of the top 10 grossing movies in the world were sequels, including space adventure Star Wars: The Force Awakens, dino thriller Jurassic World and superhero flick Avengers: Age Of Ultron.

In Singapore, there was even more love for sequels as they took up eight of the top 10 spots.

Still, industry insiders say, they come with their own challenges.

The Fox spokesman points out that the weight of expectations is heavier with sequels. "You have to build on the foundation of the previous titles and create a bigger story with better visual effects so as not to disappoint the fans."

Nor is it necessarily true that it is easier or cheaper to sell a sequel.

Mr Amit Malhotra, general manager of Studios Entertainment, The Walt Disney Company Southeast Asia, says: "Each film is unique and comes with its own promotional strategy, catering to different markets and audiences. Marketing for a sequel needs to take into account the fans of the original movie and still attract potential new fans."

A representative for exhibitor and distributor Golden Village says it may be easier to market sequels, especially "if the first part of the movie is good or if the franchise is very popular", as people would then be familiar with the brand.

But it is not cheaper to do so.

The Golden Village spokesman adds: "All movies are the same, it all boils down to the quality of the movie."

Meanwhile, not everyone is a fan of there being chapter after chapter of the same franchise.

Mr Leow Kwang Heng, 38, who works in banking, thinks a sequel is "pretty much an attempt to milk the success of the first movie".

Such films generally do not appeal to freelance graphic designer Quek Hong Shin, 36, either.

He says: "Sequels tend to try too hard to build on existing material. It's like the mystery and joy get extended and it gets tired."

For those who are wary or weary of sequels, well, brace yourselves, because more are headed here next year.

Already in the line-up, just to name a few, are Pitch Perfect 3, Pirates Of The Caribbean 5, Transformers 5, Resident Evil 6 and Fast And Furious 8.

While sci-fi adventure Avatar 2 has yet to hit theatres, the number of sequels has gone from two to three to four, as announced by director-producer James Cameron last month.

Looks like on this planet, at least, there is no getting away from sequels.

Sea of sequels

X-MEN: APOCALYPSE

Out: May 19

Who: James McAvoy, Michael Fassbender, Jennifer Lawrence, Oscar Isaac, Nicholas Hoult

What: Apocalypse (Isaac) is the first and most powerful mutant. His name spells his intent - he wants to build a better world from its ashes.

Watch it or skip it: Watch it. The ensemble cast is a line-up of some of the most talented actors around today and also because director Bryan Singer knows his way around an X-Men title, having helmed X-Men (2000), X2 (2003) and Days Of Future Past (2014).

Previous instalment's box-office result: X-Men: Days Of Future Past (2014) made US$748 million (S$1.01 billion).

TEENAGE MUTANT NINJA TURTLES: OUT OF THE SHADOWS

Out: June 2

Who: Megan Fox, Will Arnett, Tyler Perry

What: The Turtles, with the help of reporter April O'Neil (Fox), have to battle new mutants as well as an alien invasion threat.

Watch it or skip it: Skip it, even if you loved the turtles from their cartoon days (1987-1996). Then again, for a film that critics hated, its box-office results are impressive enough for the film executives to exclaim "cowabunga".

Previous instalment's box-office result: Teenage Mutant Ninja Turtles (2014) made US$493 million.

THE CONJURING 2

Out: June 9

Who: Vera Farmiga, Patrick Wilson

What: Paranormal investigators Ed (Wilson) and Lorraine Warren (Farmiga) return from the first film to investigate poltergeist activity at a council house in Enfield, England.

Watch it or skip it: Watch it, if The Conjuring (2013) or Insidious (2011) or Saw (2004) pushed your buttons as Malaysia-born director James Wan, who was behind those titles, is also at the helm for this sequel.

Previous instalment's box-office result: The Conjuring (2013) made US$318 million.

FINDING DORY

Out: June 16

Who: Ellen DeGeneres, Albert Brooks, Diane Keaton, Eugene Levy

What: Forgetful Dory (DeGeneres), a Pacific regal blue tang, sets out in search of her family.

Watch it or skip it: Watch it, definitely. Dory was the breakout star of Pixar's popular Finding Nemo (2003) and, given the time it took this follow-up to come along, you know that this was no rush job to cash in on the beloved original.

Previous instalment's box-office result: Finding Nemo (2003) made US$937 million.

NOW YOU SEE ME 2

Out: June 16

Who: Jesse Eisenberg, Mark Ruffalo, Dave Franco, Daniel Radcliffe, Jay Chou

What: The brash illusionists called the Four Horsemen attempt another dangerous heist.

Watch it or skip it: Watch it, because the first film was such an entertaining romp. Also, Harry Potter fans get their fix of seeing Radcliffe in a flick about magic, while Jay Chou fans get to see him indulge in his well-known love of magic.

Previous instalment's box-office result: Now You See Me (2013) made US$352 million.

INDEPENDENCE DAY: RESURGENCE

Out: June 23

Who: Liam Hemsworth, Jeff Goldblum, Bill Pullman, Angelababy

What: Twenty years after the alien invasion of the first film, the human race is under threat once more from a larger and more powerful fleet.

Watch it or skip it: Watch it. The original movie obliterated the competition to take the top spot at the global box-office in 1996. Advancements in technology should make for more impressive special effects this time around (including the widely circulated "destruction" of Marina Bay Sands), though probably not advanced enough for a computer virus to be transferred from a Mac computer to an alien system - which was how mankind inexplicably won the day in the first film.

Previous instalment's box-office result: Independence Day (1996) made US$817 million.

ICE AGE: COLLISION COURSE

Out: June 30

Who: Ray Romano, John Leguizamo, Denis Leary, Queen Latifah

What: In this fifth instalment, woolly mammoth Manny (Romano), ground sloth Sid (Leguizamo), saber- tooth tiger Diego (Leary), one-eyed weasel Buck (above, Simon Pegg) and company set off on the road once more to avoid the perils of destruction.

Watch it or skip it: Skip it. With each successive film, the adventures of the Ice Age gang get more preposterous and less engaging, as evidenced by the sliding scores on review-aggregating website Rotten Tomatoes. Time to put this franchise into deep freeze.

Previous instalment's box-office result: Ice Age: Continental Drift (2012) made US$877 million.

COLD WAR 2

Out: July 7

Who: Aaron Kwok, Tony Leung Ka Fai, Chow Yun Fat, Charlie Young, Eddie Peng

What: Co-directors Longman Leung and Sunny Luk extend their cop thriller by adding Chow to the mix as the main antagonist.

Watch it or skip it: Watch it - after all, those who watched the first movie need to know the resolution to the cliffhanger ending of part 1, the highest-grossing Hong Kong film in the territory in 2012.

Previous instalment's box-office result: Cold War (2012) made US$50 million.

THE PURGE: ELECTION YEAR

Out: July 14

Who: Frank Grillo, Elizabeth Mitchell

What: Senator Roan (Mitchell) wants to eliminate the Purge, an annual occasion when criminals run wild legally for a 12-hour period. But first, she must survive the night along with sergeant Barnes (Grillo).

Watch it or skip it: Skip it. This sounds like a retread of the second instalment Anarchy (2014), in which Grillo and a ragtag group try to survive on the streets.

Previous instalment's box-office result: The Purge: Anarchy (2014) made US$112 million.

STAR TREK BEYOND

Out: July 21

Who: Chris Pine, Zachary Quinto, Simon Pegg, John Cho, Zoe Saldana

What: The crew of the USS Enterprise is stranded on a hostile planet after their ship is destroyed.

Watch it or skip it: Watch it. This rebooted franchise of a beloved sci-fi property has been both smart and sexy. The first two instalments, Star Trek (2009) and Star Trek Into Darkness (2013), did well on reviewaggregating websites.

Also, there is the curiosity factor: Will Justin "Fast-And-Furious" Lin be able to rev up the series after taking over the reins from J. J. Abrams?

Previous instalment's box-office result: Star Trek Into Darkness (2013) made US$467 million.

JASON BOURNE

Out: July 28

Who: Matt Damon, Julia Stiles, Alicia Vikander

What: Superspy Jason Bourne (Damon) resurfaces several years after his disappearance at the end of The Bourne Ultimatum (2007).

Watch or skip it: Watch it. The franchise's original star Damon - who sat out film No. 4 (2012's The Bourne Legacy) and was replaced as the main man by Jeremy Renner playing a different character - is back as the buff and indestructible agent who is not James Bond.

Director Paul Greengrass, who helmed the critical and popular hits that were films No. 2 and No. 3, also returns to the fray.

Previous instalment's box-office result: The Bourne Legacy (2012) made US$276 million.

ALICE THROUGH THE LOOKING GLASS

Out: Aug 11

Who: Johnny Depp, Anne Hathaway, Mia Wasikowska, Helena Bonham Carter

What: The sequel to Alice In Wonderland is based on Lewis Carroll's book Through The Looking-Glass (1871), in which the titular heroine (Wasikowska) returns to the fantastical world of Underland, where she has to help her friend The Mad Hatter (Depp).

Watch or skip it: Skip it. The first movie was largely a CGI extravaganza bereft of wonder, as charged by some critics. Also, visionary film-maker Tim Burton is not returning to direct this, ceding the reins to James Bobin (The Muppets, 2011).

The only surprising thing about this sequel is that it took so long to arrive, given how much money the first one made.

Previous instalment's box-office result: Alice In Wonderland (2010) made US$1.03 billion.

MECHANIC: RESURRECTION

Out: Sept 1

Who: Jason Statham, Jessica Alba, Tommy Lee Jones, Michelle Yeoh

What: Arthur Bishop (Statham) is forced to come out of retirement as a contract killer when the love of his life is kidnapped.

Watch it or skip it: Skip it. The original was a middling B-grade movie. Despite the overhaul of director and scriptwriters for this work, its fate seems unlikely to be different.

Previous instalment's box-office result: The Mechanic (2011) made US$62 million.

BRIDGET JONES'S BABY

Out: Sept 15

Who: Renee Zellweger, Colin Firth, Patrick Dempsey

What: Bridget Jones (Zellweger) is pregnant, but she is not sure who the father is - Mark Darcy (Firth) or the new man in the picture, dashing American Jack Qwant (Dempsey)?

Watch it or skip it: Watch it. Sharon Maguire, who directed the first, charming movie in 2001, is back at the helm, even if Hugh Grant has exited the series.

Also, admit it, you are curious about Zellweger's looks after she appeared at an awards event in 2014 looking unrecognisable.

Previous instalment's box-office result: Bridget Jones: The Edge Of Reason (2004) made US$263 million.

UNDERWORLD: BLOOD WARS

Out: Oct 13

Who: Kate Beckinsale, Theo James, Tobias Menzies

What: Beckinsale reprises her role as Selene, a vampire warrior, for the fifth instalment.

Watch or skip it: Skip it, though it is impressive how a title with consistently bad reviews has managed to build up a franchise of five titles.

Previous instalment's box-office result: Underworld: Awakening (2012) made US$160 million.

JACK REACHER: NEVER GO BACK

Out: Oct 27

Who: Tom Cruise, Cobie Smulders

What: The sequel is based on the 2013 Jack Reacher novel by Lee Child, in which the protagonist is accused of a 16-year-old homicide - and he may also be the father of a teenage girl.

Watch or skip it: Skip it. Cruise already has one mega successful franchise, Mission: Impossible. Do we really need to see him in another one with potentially 18 more films? That is how many books there are in the series about the mercenary/vigilante so far.

Previous instalment's box-office result: Jack Reacher (2012) made US$218 million.

RINGS

Out: Nov 10

Who: Matilda Lutz, Alex Roe, Johnny Galecki

What: A cursed video tape makes its way to a college campus.

Watch or skip it: Skip it. The director and cast of the first two films included Gore Verbinski (Pirates Of The Caribbean: The Curse Of The Black Pearl, 2003), Hideo Nakata (director of the 1998 original Japanese horror Ringu) and stars such as Naomi Watts and Sissy Spacek.

In contrast, the biggest name in Rings is Galecki, who starred in the sitcom Roseanne from 1992 to 1997.

Do not let this movie franchise run rings around you.

Previous instalment's box-office result: The Ring Two (2005) made US$161 million. •

•Release dates are scheduled to change.