By the end of 1979 ELO had reached the peak of their stardom, selling millions of albums and singles, and even inspiring a parody/tribute song on the Randy Newman album Born Again, titled "The Story of a Rock and Roll Band". During 1979 Jeff Lynne also turned down an invitation for ELO to headline the August 1979 Knebworth Festival concerts. That allowed Led Zeppelin the chance to headline instead. In 1980 Jeff Lynne was asked to write for the soundtrack of the musical film Xanadu, with the other half written by John Farrar and performed by the film's star Olivia Newton-John. The movie performed poorly at the box office, but the soundtrack did exceptionally well, eventually going double platinum. The album spawned hit singles from both Newton-John ("Magic", a #1 hit in the United States, and "Suddenly" with Cliff Richard) and ELO ("I'm Alive", which went gold, "All Over the World" and "Don't Walk Away"). The title track, performed by both Newton-John and ELO, is ELO's only song to top the singles chart in the United Kingdom. More than a quarter of a century later, Xanadu, a Broadway musical, based on the film, opened on 10 July 2007 at the Helen Hayes Theatre to uniformly good reviews. It received 4 Tony Award nominations. The musical received its UK premiere in London in October 2015. Casey Kasem called The Electric Light Orchestra a "7-man supergroup" and "amazing" for hitting The Top 40 a remarkable 6 times in a one-year period from August 1979 to August 1980 before playing "All Over the World" at #23
In 1981, ELO's sound changed again with the science fiction concept album Time, a throwback to earlier, more progressive rock albums like Eldorado. With the string section now departed, synthesisers took a dominating role, as was the trend in the larger music scene of the time; although studio strings were present on some of the tracks conducted by Rainer Pietsch, the overall soundscape had a more electronic feel in keeping with the futuristic nature of the album. Time topped the UK charts for two weeks and was the last ELO studio album to be certified platinum in the United Kingdom until Alone in the Universe in 2015. Singles from the album included "Hold On Tight", "Twilight", "The Way Life's Meant to Be", "Here Is the News" and "Ticket to the Moon". The band embarked on their last world tour to promote the LP. For the tour Kaminski returned to the line-up on violin, whilst synthesiser players Louis Clark and Dave Morgan also joined the band.