Is “Watchmen,” Zack Snyder’s (“300”) adaptation of the best-selling comic, brutally dark? Yes. Could it stand to lose 30 minutes of runtime? Also, yes. Was it overly ambitious for Snyder to create a movie out of source material that famed-director Terry Gilliam once called “unfilmable?” Possibly. But, is “Watchmen” also one of the most engrossing film experiences in recent memory? Absolutely.

“Watchmen” takes place in an alternate vision of Cold War America. It is 1985 and still-President Nixon has won the Vietnam War with the help of masked crime-fighters and the superhuman Dr. Manhattan (Billy Crudup). When one of these heros is murdered, it launches the vigilante Rorschach (Jackie Earle Haley) into an investigation of a sinister conspiracy.

The main strengths of “Watchmen” are the arresting visuals Snyder, who used the comic’s original panels as storyboards, brings to the screen. Each shot is a painting full of rich color and breathtakingly composed. It is impossible not to be drawn into a film this visually appealing, especially during the magnificent opening credit sequence.

It is the look of the “Watchmen” that lets it sail through a number of rough patches that could have sunk a less visually-appealing film. The dialogue is occasionally stiff and the pace of the film lags at points – both due to the film sticking faithfully to the source material.

There is also the film’s occasionally oppressive violence and gloom. If last year’s “The Dark Knight” was the superhero genre’s darkest film to-date, then it was simply preparing audiences for “Watchmen.” In just under three hours, the film deals with rape, child murder, cold-blooded killings, broken families, childhood traumas, the destruction of the planet and the end of humanity.

Fortunately, as the film threatens to fly out of reach with the weighty subjects of Cold War morals and mutually-assured destruction, there are the characters of Night Owl II (Patrick Wilson) and Silk Spectre II (Malin Akerman) to ground it. Their relationship and personal turmoils give the audience something firm to grab hold of.

Wilson is a special relief. His washed-up superhero is a gone-to-pot, dorky everyman and watching him awkwardly reigniting his relationship with Silk Spectre II provides some of the most enjoyable moments in “Watchmen.”

“Watchmen,” despite its flaws, deserves to be seen simply for the joy of watching the unfilmable film play out so gorgeously in front of your eyes.