The Steelmen had been looking to secure a sixth successive win in the top-flight for the first time in 70 years, but it was the visitors that ended their hoodoo thanks to an emphatic second-half performance.
Motherwell dominated the early stages with Ross McCormack causing the visiting defence all sorts of problems.
He sent a teasing cross in for Chris Porter only for the striker to head the ball over the bar and then took matters into his own hands with a stinging drive that Tim Krul held.
Krul was involved in the action again midway through the half when he denied David Clarkson with a sharp save. The shot rounded off a flowing move down the Motherwell right involving Stephen Hughes and Porter.
Falkirk had offered little until the final ten minutes of the half when Scott Arfield fired a 25-yard shot over. It wasn't until the 40th minute that home keeper Graeme Smith had to make his first save from a weak Michael Higdon header.
Falkirk built on their efforts in the closing stages of the first half by taking the lead early in the second period. Graham Barrett found space on the left and his cross to the far post was met by the head of Higdon.
Motherwell almost responded immediately when McCormack's free-kick reached Hughes in the box but his toe-poke towards goal was kept out by Krul.
On the hour mark Falkirk doubled their lead with Higdon once again doing the damage. He met a Pedro Moutinho corner first time on the volley and his effort flew past Graeme Smith in the home goal.
Things only got better for Falkirk and they made it 3-0 on 65 minutes. Steve Thomson turned on the edge of the box and fed the ball into the path of Patrick Cregg who gratefully swept his 12-yard shot home.
Both sides continued to create chances with Motherwell's substitutes going close to pulling a goal back. Jamie Murphy saw an angled drive saved by Krul before Darren Smith had a volley saved by the keeper.
At the other end Moutinho left Stephen Craigan for dead wide on the left before cutting inside and firing in a stinging shot which was well saved by Graeme Smith.
In the final minute it was only the crossbar that prevented Falkirk from making it 4-0 as Dean Holden's rising effort beat Graeme Smith before crashing clear.
Despite that the Bairns headed back to Falkirk with an excellent three points.