Although the film was a box office disappointment in the United States, it was a huge hit in Asia. Somewhere in Time (1980) is one of the highest-grossing films in China, and played in Hong Kong for eighteen months.
While Christopher Reeve was filming this movie, the local theater decided to show his latest hit Superman (1978). Many of the "Somewhere" cast joined the locals for the event. Early into the screening, the sound went out. Reeve, who was seated next to Jane Seymour, stood up in the audience and delivered all the lines.
According to producer Stephen Deutsch, Christopher Reeve's agent literally laughed in his face when he was told the salary his client would be offered for the role (in what would be his first role after his star-making performance in the smash hit Superman (1978)). He refused to read the script or allow Reeve to hear about it. Knowing he could not proceed without a star, Deutsch clandestinely slipped Reeve the script in his hotel room. Reeve called the next day and said he loved the script and would accept the role. Reeve told Deutsch that another reason why he accepted was that the other project he was being offered at the time was a viking movie.
The moment when Richard Collier first sees the portrait of Elise McKenna in the film was also the first time Christopher Reeve saw the portrait. Reeve did not want to see the portrait ahead of time, which helped meet the director's objective of getting a genuine reaction from him when he first sees the portrait as Richard.
As of 2008, the numbers of Elise McKenna and Richard Collier's rooms do not exist at the Grand Hotel. However, there is a Somewhere in Time suite.
Richard Matheson: The film's screenwriter and also its source novelist as an astonished man in 1912.