Under the orders of rival expert Paul Laidlaw, the Bedford based auctioneer overvalued a lighter and pretended to receive offers in the thousands.
Clutching his chest at the “huge unexpected find”, it was soon revealed to Thomas that he had been the victim of a BBC prank.
Looking excited, the auctioneer gasped: “Interesting lot this. Had a fair bit of interest this. I’ve got loads of bids here.
“Start this at £1,100. At £1,100 now,” prompting Paul, who was in on the joke, to scream: “How much?”
The auctioneer smirked and said: “I’m just joking. I’m sorry. Just trying to wind you all up.”
Voicing the show, antiques expert Tim Wonnacott said: “Auctioneers aren’t normally known for laying tricks. Just as well Thomas is such a good sport.”
Revealing the true bid for the item, Thomas look deflated after she announced: “I have got just a fiver starting point now.”
Tim added: “Ah that’s more like it. What a cheeky soul,” as Thomas probed Paul: “Did you ask her to do that? Ah you good man. That is hilarious.”
Selling for £22, Thomas made a loss of £13 on the lighter, but wasn’t left disheartened by the situation.
He said: “For a fleeting moment I thought to myself, ‘Poor Paul.’ Do you know, that’s what went through my mind, ‘Poor Paul,’” leaving the professional to add: “Now I feel terrible.”
Following the end of the auction, Thomas gave Paul a few friendly punches, pointed his finger and said: “That joke you played. That was fabulous. I took it hook line and sinker.”
However, Paul wasn’t apologetic for the prank, adding: “I would say sorry… but I’m not.”
Antiques Road Trip continues this Monday on BBC One at 5.20pm.