The Made in Chelsea star got on board to officially launch the 62nd event in Docklands - and even made sure her royal blue dress and ruby red heels matched its colour scheme.
Boat show chairman Peter Gordon handed her a pair of scissors - emblazoned with the name of the C4 reality show - for her to nip the tape and declare it an “absolute pleasure” to announce the nine-day extravaganza open.
Meanwhile, Peter quipped: “During the series of press interviews this week I’ve learned Lucy knows a whole lot more about boats than you’d think.”
Meanwhile, Downtown Abbey favourite Hugh was eager to reminisce about his childhood sailing adventures while revealing the Sunseeker stand and breaking the bottle at the official naming ceremony for the first 131 Yacht model.
It is the largest boat to be launched at the show.
After he was referred to as a “great British export” by the Sunseeker team and brand founder, Robert Braithwaite, he said: “Downton has been an extraordinarily worldwide success so both our products have travelled the world flying the flag for Britain.
“It’s wonderful to be back here - I used to go to the Boat Show with my dad when it used to be at Earl’s Court.
“I spent a lot of my childhood in Blackheath and my favourite trip was always, instead of taking the train to Waterloo East, was going by boat to Charing Cross Pier.
“And it’s a great way to see the city especially with the re-development in east London.
“I remember standing in Greenwich Park and seeing the wasteland opposite me - now there we’ve got Canary Wharf.”
Meanwhile Robert added he hoped to “inspire” youngsters with the vast collection of Sunseeker yachts.
The show also features luxury vessels the Princess 60 and Princess V58 Open, both handcrafted in Plymouth,
a well as almost 400 more models.
Boating enthusiasts can also pick up products from more than 300 companies worldwide.
Brands including Arthur Beale, Suzuki GB and Lewmar will be on-sale while hands-on activities can be found in the Mediterranean Bay, which will host live demonstrations, as well as a 60’s Revival show celebrating boating highlights from a bygone era.
Talks and discussions by industry experts will take place throughout the showcase.
Until January 17, from 10am, from £15, Excel.