Environmentally responsible behavior has not always been a basic requirement for filming on location in a national park. If you don't believe it, watch Forever, Darling. OMG!

In February 1956, Metro-Goldwyn-Mayer (MGM) released Forever, Darling, a fantasy comedy featuring Lucille Ball and Desi Arnaz. The two famed comedians, stars of the super-popular CBS-TV Monday night comedy series "I Love Lucy" (1951-1957) and a married couple in real life, worked on the film while on a hiatus from the TV series.

Ball and Arnaz had their own production studio, Desilu, and Forever, Darling was a joint MGM-Desilu production. This was Desilu's first venture into feature film production -- a testing of the waters, as it were. A second MGM-Desilu collaboration was to follow if this one worked out. Alas, it did not work out.

Forever, Darling was a flop. Citics savaged it, audiences stayed away in droves, and the film barely recovered its production costs (around $1.4 million). These results were so disappointing that MGM dropped its tentative plans to co-produce a second feature film with Desilu. Arnaz, for his part, decided not to create a feature film division of Desilu.

If Forever, Darling was not exactly what you would call a successful film, it certainly was an interesting one. One of the things that made it interesting was its abundance of footage shot on location in Yosemite National Park. To the audiences of today, what they did while in the park is even more interesting.

How the film couple ended up in Yosemite takes a little explaining. The plot has Susan Vega (Ball) married to a chemical engineer named Lorenzo Xavier Vega (Arnaz). Lorenzo (aka "Larry") works for Finlay Vega Chemical Company, and his current challenge is to thoroughly field-test a super-powerful new insecticide code-named "383."

How powerful is 383? "We think it'll make DDT look like talcum powder," says a Finlay executive. Why produce such a potent poison? "The aim of scientists is to make the world a better place to live in," says another. And to do that, of course, you need to kill bad bugs very dead, very quickly. The chemists believe that 383 will kill mosquito larvae in about four seconds.

Lorenzo figures that he will have to spend two years in the field to give 383 a proper workout under field conditions. When he tells Susan, she begs him to let her come with him. Susan's Guardian Angel (hey, I told you that this is a fantasy comedy!) has counseled her that she must take a greater interest in Lorenzo's career if she is to re-inject zest into their flagging five year-old marriage. Lorenzo acquiesces, and off they go to rough it in the semi-wilds. They will camp in a tent, and Lorenzo will dump 383 into waterways and see what happens. Susan hopes that the trip will be a second honeymoon. Lorenzo hopes that 383 will make him rich.

Hollywood being Hollywood, the film has the Vegas camping beside the Merced River in Yosemite Valley, with Yosemite Falls supplying the scenic backdrop. What shortly ensues is quite possibly the single most environmentally irresponsible episode in the long history of filming on location in the national parks. With Susan providing spectacularly inept assistance, Lorenzo sets about to dump a batch of 383 into the Merced River. Yes; our hero is determined to see if he can adequately poison the trademark river in one of America's most cherished national parks. As they say, it seemed like a good idea at the time.

Susan's Guardian Angel tinkers with the mixture, which is supposed to be 99 percent talc/inactive ingredients, so the experiment doesn't go out exactly as planned. If you want to see the ending, you'll need to watch the film for yourself. I got my copy from Netflix, and the last time I looked you could buy a copy from Amazon.com for about three bucks plus shipping.

If you don't want to watch the whole thing, you can see the movie trailer at this site.

Postscript: Lucy and Desi were not the first choice for the starring roles in Forever, Darling. In fact, they weren't even the second choice. Screen writer Helen Deutsch wrote the original script in the 1940s with Myrna Loy and William Powell in mind, but that idea fizzled. Later, a deal to have Katherine Hepburn and Spencer Tracy play the lead roles was in the works, but that fell through too. Lucy and Desi were cast as the Vegas only after MGM decided to revive the project for another go-around..