The Fat Controller was joined in the West End by Mo Farah, Stacey Solomon and others at Vue Cinema, Leicester Square.
Prior to the release (3rd September), fans got the chance to see Thomas on the big screen at 70 Vue cinemas across the country on 1st and 2nd September.
‘Blue Mountain Mystery’ is Thomas & Friends’ fifth direct-to-DVD special.
Celebrities attending the blue carpet premiere included double Olympic Gold medallist Mo Farah with his daughter Rhianna, England Cricket star James Anderson, and Wolves midfielder Jamie O’Hara with his wife Danielle Lloyd and son Archie.
Other names included TV stars Stacey Solomon and Kate Garraway, EastEnders actress Jo Joyner, beauty entrepreneur Jo Wood, comediennes Katherine Ryan and Shappi Khorsandi, and actor Shaun Dooley.
Also present were Channel Five milkshake! presenters Kemi Majeks and Olivia Birchenough.