Len, 73, was a firm favourite on the BBC dancing competition, acting as head judge for 12 years before bowing out in an emotional finale last year.
In a shockingly frank confession, the star admitted: “Totally honest, some of the celebrities we had on the show I didn’t actually recognise at first.”
Hitting out at the modern ‘celebrity’ world of showbiz, Len told Radio Times: “There are so many now. So many celebrities!”
Strictly Come Dancing fans have gone into hyperdrive over the past week, with the first contestant for the 2017 line-up being announced as Mollie King last week.
The Saturdays singer, 35, was soon joined by EastEnders star Davood Ghadami, 35, and This Morning presenter Ruth Langsford, 47.
Former Emmerdale actress Gemma Atkinson, 32, Reverend Richard Coles, 55, Holby City star Joe McFadden, 41, and Sunday Brunch host Simon Rimmer, 52, have also been confirmed for the hotly-anticipated fifteenth series.
Earlier today, X Factor star and ex-JLS singer Aston Merrygold, 29, was unveiled as the eighth contestant set for Strictly 2017.
However, the news has caused some controversy on social media, as fans of the show flooded to Twitter to express their fury at Aston’s previous dance experience.
Many have hit out at show bosses for his “unfair advantage” as the singer has previously served as a judge on Sky 1’s Got To Dance, with one tweeting: “It’s not just previous dance ‘experience’, he’s a trained dancer/performer/dance judge.”
“He’s been a judge on a dancing competition,” another blasted. “How is this fair?!”
Read the full interview in this week’s Radio Times – out now.
Strictly Come Dancing returns to BBC next month.