Directed by Lost’s J. J. Abrams and starring Winona Ryder and Eric Bana, the movie is a prequel chronicling the early days of Captain Kirk and the U.S.S. Enterprise crew members, reported a source on the highly protected set, where actors playing alien creatures are forced by producers to cover themselves with enormous umbrellas when they walk from location to location.

Mr. Nimoy, who has played Kirk’s lovable Vulcan sidekick Spock since the dawn of Trek and has recently developed a second career photographing naked ladies, makes several cameos in the film in the form of a spirit, according to the source; on this, the veteran actor’s last day of filming, Mr. Abrams gave a speech about what an honor it was to have worked with him. (The original Kirk, William Shatner, has been left out of the production and is reportedly bristling about it.)

A group of set designers and grips were overheard discussing Mr. Nimoy’s fall.

“You know the sets are so dark and he’s an old guy,” said a makeup artist of the actor, who turns 77 on Wednesday, March 26. “He must have just tripped.”

“There was some talk about using a double and how they were making a wig for the double, so that the guy would look more like Leonard Nimoy,” said the original source. “But then they ended up using Leonard Nimoy.”

A male crew member eased everyone’s nerves. “Well, you know, with CGI, you know they can fix that nose right up, have it looking normal,” he said. Phew!

Mr. Nimoy’s agent had no comment on the incident.