The story was that Francis Rossi and Rick Parfitt turned up in the Rover's Return, having played a concert in the Weatherfield area. Les Battersby, who was known to be a big Quo fan, was overjoyed – but his joy soon turned to anguish as the two rock stars assaulted him and left him lying in the street. It turned out that they recognised him as the lunatic who'd jumped onto the stage at a concert some twenty years previously, causing a permanent neck injury to Rossi.
Les's paramour Cilla Brown (who was at the time involved in a complicated love triangle with Les and Janice, the love of his life) spotted an opportunity to cash in, and encouraged Les to sue for compensation. But much to Cilla's chagrin, the band offered to play at their forthcoming wedding instead of stumping up readies. This of course was too good an offer for Les to turn down.
In real life, it's not clear whether the entire band turned up for the recording. According to Wikipedia it was just Rossi and Parfitt – backed, presumably, by session men. In the broadcast footage, they state (through gritted teeth) that they wish to be announced as Status Quo.
© Haydn Thompson 2020