Winter is fast approaching, and that means the arrival of several things -- colder weather, lots of snow, and various illnesses. Some people are stricken by common colds, others fight maladies like the flu or pneumonia. The winter/holiday season also carries one more large piece of baggage -- the plethora of big-ticket movies that open between mid-November and Christmas. This isn't a discourse on the Hollywood system; I know full well that all of these films are released to further line the pockets of the filmmakers and studio moguls. However, going back to the theme of disease, the movie industry suffers from a terminal condition that worsens at this time of year -- sequelitis.Obviously, sequels are released year round, but in November and December, watch out, because the sequels come in greater numbers than at any other point in the calendar ... especially this year.

Before delving into this year's offerings, let's reflect on past cases of sequelitis. Sometimes, the second film in a series surpasses the first, even if the initial movie is hailed as one of the greatest of all time ("The Godfather, Part II"). Other times, a sequel can be a total disaster, no matter how good the intentions are, plaguing a film series forever ("The Godfather, Part III"). Putting aside the chastising of Francis Ford "Why-did-I-cast-my-daughter?" Coppola, there are some general symptoms of sequelitis.

First, sequels tend to appear most in the sci-fi/fantasy and action/adventure genres, as well as some comedies. Remember the "Batman" movies? Well, the first, with Michael Keaton, is pretty good. "Batman Returns" is not as entertaining, but still an adequate follow-up picture. But once they started to replace the title character and director, things got out of hand with flat one-liner scripts and slapstick thugs. Let's not reminisce on "Batman & Robin." Now, "Star Wars" has two good sequels, but it's also one continuing story. But I'm not even going to touch this 'prequel' thing that George Lucas is dragging us into now, so let's just drop it.

There are five installments in the "Rocky" series, but none compare to the first, not even the Cold War/"Why-can't-we-all-get-along?" fourth. Does anybody even remember that Rocky doesn't win until the second film, or anything besides the song from the third? In fact, did anybody see "Rocky V" at all? The answer to all of these questions is a definitive no. While the original "Rocky" is beloved and a great inspirational tale, the sum total of four sequels is a bad song and Mr. T.

Comedic sequels are probably the most dangerous of them all, because there is no acting more difficult than being funny, and jokes can be repeated only so many times before they head off to the graveyard. Therefore, for a comedy series to avert sequelitis, it must bring new and better jokes to each edition. "Caddyshack" is one of the funniest pictures ever, but nobody asked for the horrors of "Caddyshack 2." And, considering that none of the recent big-ticket comedies, like those starring Adam Sandler or Rob Schneider, are very funny, imagine how bad sequels to those films would be. This winter, we are also being subjugated to "Analyze That," a continuation of the Billy Crystal/Robert DeNiro vehicle "Analyze This." It looks promising, but I am dreading that it will use recycled material.

This year, sequelitis is getting bad. Already we have seen the release of "The Santa Clause 2" more than half a decade after the first. In all honesty, there should be rules governing the time frames for making sequels. If they can't come up with a second part within two years, then there should be no sequel. Seriously, it should not take six years to put Tim Allen back into a Santa suit. This holiday season also marks the tenth installment of "Star Trek," a franchise that should have been laid to rest several films ago.

Of course, not all sequels are necessarily bad. The second "Harry Potter" film opened to better reviews than its predecessor and is enjoying similar box office success. "The Two Towers," the second installment in "The Lord of the Rings," also looks very promising. However, these two series are different than other multi-picture stories. First of all they are based upon series of books, and secondly, the casts and crews were signed to multi-picture deals. The sequels will hit theaters inevitably, regardless of the performance of their predecessors.

And, of course this past weekend the king of all series released its 20th incarnation. "Die Another Day," the latest installment of over forty years of Bond movies opened to great success. But Bond movies have exceptions too. Some have been bad -- like all of those starring Roger Moore -- while others stand out. But these movies enjoy the status of being able to stand alone as individual pictures. There are twenty Bond movies, but they are hardly sequential, so sequelitis is not a real issue.

Anyway you slice it, Hollywood tries to cash in on its success; that's not being disputed. But, when you go to the movies this winter, be mindful for which film you shell out your money, especially if it has a number at the end of its title. Sequelitis can let the producer laugh all the way to the bank while the moviegoer leaves the theater pondering "Didn't they do that in the first one?" Be careful.