By the time of filming, Sir Christopher Lee had become famous as Count Dracula. When he and Billy Wilder walked on the shores of Loch Ness at dusk, with bats circling overhead, Wilder said to him, "You must feel quite at home here."
With a 260-page script and a budget of $10 million, this was set to be a two hour and forty-five-minute Road Show movie with an intermission for comfort. It was to be the "Big One" for Billy Wilder. The shooting schedule ran for six months and resulted in a rough-cut that came in at three hours and twenty minutes. The movie was originally structured as a series of very specifically structured linked episodes, each with a particular title and theme. The opening sequence was to feature Watson's grandson in London claiming his inherited dispatch box from Cox & Company, and there was also a flashback to Holmes' Oxford days to explain his distrust of women. All were shot, but deleted from the final print. So what happened? Well, it appears that United Artists suffered several major movie flops in 1969 that pretty much scuppered the road show format for Wilder's massive project. Studio execs ordered the movie to be cut to fill a regular theatrical running time, whittling it down to a two hour and five-minute version. The episodic format made the pruning process relatively simple, so cut were the opening sequence, the Oxford flashback and two full episodes titled "The Dreadful Business of the Naked Honeymooners" at fifteen minutes, and "The Curious Case of the Upside Down Room" at thirty minutes. We can only hope that the full footage can one day be restored, although a full print is not currently thought to exist.
Originally, the scenes featuring the Loch Ness Monster were intended to be filmed in the actual Loch. A life-size prop was built which had several Nessie-like humps used to disguise flotation devices. The humps were removed, however, at Billy Wilder's request. Unfortunately, during a test run in Loch Ness, the Monster-prop sank and was never recovered. A second prop, a miniature with just the head and neck, was built, but was only filmed inside a studio tank. Geneviève Page said of this in the biography "Nobody's Perfect: Billy Wilder" by Charlotte Chandler): "When we lost our Loch Ness monster, he (Wilder) wasn't too concerned, even though he was also the producer. He was more concerned about how the man who made it felt when all his work sank to the bottom of the Loch Ness. He went over and comforted him." The original monster prop was located on the bottom of Loch Ness in April 2016 during a survey of the loch by an underwater robot. (See below.)
Writer and director Billy Wilder said of this movie in the book "Conversations with Wilder" by Cameron Crowe, "when I came back (from Paris), it was an absolute disaster, the way it was cut. The whole prologue was cut, a half-sequence was cut. I had tears in my eyes as I looked at the thing. It was the most elegant picture I've ever shot."
When Sir Robert Stephens asked Billy Wilder how to play Sherlock Holmes, Wilder replied, "You must play it like Hamlet. And you must not put on one pound of weight. I want you to look like a pencil."