The show must go on, is the old saying, and that is true of the opening night of the long delayed premiere of Back To The Future: The Musical which is debuting after a long Covid-enforced wait. However, the pandemic has still managed to cause some opening night chaos as actor Roger Bart, who plays Doc Brown in the production based on the 1985 sic-fi comedy, has been forced to sit out the performance after testing positive for Covid. The show arrives in the West End of London with Bart's understudy Mark Oxtoby having a huge opportunity in the unfortunate circumstances as he appears alongside Olly Dobson as Marty McFly.

The Back to The Future musical is set to run through until April 2022, and features new songs and music by Alan Silvestri, who composed the score for the original movie trilogy, and includes lyrics by Glen Ballard, who worked on Robert Zemeckis' The Polar Express and Ghost: The Musical.

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Roger Bart spoke in London Theatre about what it was like to step into the shoes of Christopher Lloyd, who played Doc Brown in the original movies and numerous tie-in cameo appearances. "How does one fill the shoes of the iconic and amazing Christopher Lloyd in this beloved role? The simple answer is, you can't. But what a crazy dream come true to give it my best shot," Bart said, although he will not have to wait just a little longer to take that shot himself.

Of course, with this being a full blown stage musical, Doc Brown does something that he didn't in the movies - sing and dance. Bart said, "The songs in the show are a lot like long closeups in a film. It gives the audience and the actors the opportunity to really reveal many things you many not see otherwise." Bob Gale, who co-created the movie with Zemeckis, also praised Bart in the publication, saying Bart is "a wonderful talented veteran of musical theatre and a comedian in his own right. He took some aspects of Doc Brown from the movie, but he really added another dimension to Doc that we don't really get to see because the relationship between Marty and Doc in the musical is a lot warmer."

The official description of the musical reads: "Welcome to Hill Valley! Take an electrifying ride back in time as the 1985 blockbuster film and pop culture phenomenon arrives in London's West End as a groundbreaking new musical adventure! When Marty McFly finds himself transported back to 1955 in a time machine built by the eccentric scientist Doc Brown, he accidentally changes the course of history. Now he's in a race against time to fix the present, escape the past and send himself... back to the future. Adapting this iconic story for the stage are the movie's creators Bob Gale (Back to the Future trilogy) and Robert Zemeckis (Forrest Gump).

The production features original music by multi-Grammy winners Alan Silvestri (Avengers: Endgame) and Glen Ballard (Michael Jackson's Man in the Mirror), alongside hit songs from the movie including The Power of Love, Johnny B. Goode, Earth Angel and Back in Time. Tony Award-winning director John Rando leads the Tony and Olivier Award-winning creative team, with Tim Hatley designing set and costumes. When BACK TO THE FUTURE: THE MUSICAL hits 88mph, you're gonna see some serious... entertainment."