Owen Eames' first Falkirk goal earned a deserved first Scottish Premiership win of the season against haphazard Hearts, who missed the chance to move up to second.
On-loan Derby County midfielder Eames capitalised on a horror ball across the backline from Hearts captain Harry Milne to finish in-off a post.
John McGlynn's energetic Falkirk were in front after eight minutes, courtesy of Ben Krauhaus' cool finish after a switch-off in the visiting defence. But recalled Scotland striker James Wilson hauled Hearts level 15 minutes later.
The teenage forward - named in Sebastien Pocognoli's first squad earlier on Tuesday - tapped in fellow call-up Josh McPake's neat cross for Wouter Vrancken's side, and he should have put in front before the break, but got his angles all wrong.
Wilson was withdrawn at half-time and his replacement, JJ Williams, scuffed a golden opportunity for Hearts - who would have leapfrogged Rangers on goal difference with a draw - as Falkirk continued to look a threat themselves.
Eames inexplicably hesitated in taking a shot, while visiting goalkeeper Beau Reus brilliantly denied Finley Barbrook with his boot.
But, the Hearts goalkeeper could do nothing to deny the winner as Falkirk - who could have had a third when Ethan Ross skelped an upright - defeated Hearts in the top flight for the first time in 18 years.