The burly striker collected two premium-quality goals which decided this quarter-final tie at Brockville after Andy Seaton's early goal gave last year's runners-up the confidence to exploit an apathetic St Johnstone side.
Not even Celtic or Rangers will fancy facing the combative First Division team in the semi-finals - both have been knocked out by Falkirk in recent years.
Falkirk took the scalps of three Premier League teams on their way to last year's Scottish Cup final, including Celtic. However, their manager, Alex Totten, must have harboured adding St Johnstone to that list of victims, given that the Perth club sacked him six years ago.
In fact, St Johnstone were seeking to reach the last four for the first time since Totten guided them to a semi-final in 1989, when Rangers needed a replay to triumph.
St Johnstone's unease on the heavy pitch was underlined in the 13th minute when John O'Neill was booked for a dreadful tackle on Scott Crabbe, which forced the Falkirk forward to have several minutes' treatment.
Crabbe, though, took his revenge six minutes later when he played a pivotal role in putting Falkirk ahead.
The left-back, Andy Seaton, both started and finished the move, but it was Crabbe who intelligently switched the play by transferring the ball on to Kevin McAllister on the right. The former Chelsea winger's cross was missed by Marino Keith but not by Seaton, who drilled a low shot past the goalkeeper Alan Main.
It was Main's alertness which prevented Saints from going further behind soon after when he dived bravely to prevent the rampaging Keith from scoring. St Johnstone's frustration was obvious, and Jim Weir and Philip Scott were shown yellow cards, before Falkirk left the Premier side speechless with a second goal in the 34th minute.
David Hagen's free-kick was met by Jamie McGowan and the Falkirk captain's header broke kindly to David Moss who coolly planted a right-foot volley into the corner of the net.
St Johnstone would have been dead and buried if another McGowan header had not struck the crossbar eight minutes later. O'Neill squandered a good chance to pull back a goal for St Johnstone just a minute after half time and his side was soon to regret the striker's miss when Moss scored his second in the 49th minute.
Again McAllister provided the telling cross, this time it was chested down by Keith into the path of Moss whose low left-foot shot from the edge of the area beat Main to make it 3-0.
St Johnstone's ineptness was embarrassing and only a fine save by Main in the 56th minute stopped Keith's header from increasing the gap between the sides.Reuse content