Steven Naismith's first-half hat-trick helped Hearts remain top of the Ladbrokes Premiership in manager Craig Levein's absence.
A comfortable win over St Mirren maintains the Edinburgh club's 100 per cent record on a day when they swept the opposition aside at Tynecastle Park.
The hosts sat 4-1 ahead at half-time thanks to Naismith's treble and a fine Olly Lee strike. The Scotland internationalist is the first Hearts player to score a hat-trick since Genero Zeefuik in 2015, but that was only one aspect of a swashbuckling display.
Jimmy Dunne's own goal pulled St Mirren level after Naismith's early penalty opened the scoring. Lee's left-footed volley preceded two more instinctive finishes by Naismith to put this game out of St Mirren's reach before the interval.
Whilst Levein recovered at home following a recent spell in hospital, assistant coach Austin MacPhee took charge of Hearts. He oversaw a performance which would have made the manager thoroughly proud.
Demetri Mitchell started after returning to Tynecastle on loan from Manchester United, whilst latest signing Craig Wighton had to make to with a place amongst the substitutes. He was joined by Arnaud Djoum, who was back in a matchday squad for the first time since snapping his Achilles in February.
It took Hearts just three minutes to open the scoring. After a foul by St Mirren's Jack Baird on Uche Ikpeazu inside the box, Naismith confidently stroked the resultant penalty low into the bottom corner past goalkeeper Craig Samson.
Mitchell lined up in a wide-left midfield role with Ben Garuccio behind him at left-back. The Englishman quickly began tormenting the his direct opponent, Lee Hodson. On 14 minutes, he teed up Garuccio for a vicious 20-yard drive which flew narrowly over the crossbar.
Hearts were in command at that stage, however St Mirren showed impressive resolve to level the scores on 19 minutes. Stephen McGinn and Hayden Coulson had opportunities from the inside-left position, but both pulled their shots across goal and wide of the far post before the visitors forced an equaliser.
Cammy Smith's evasive run on the left took him past Hearts full-back Michael Smith and his low cross was inadvertently turned into his own net by Dunne. Those from Paisley might have sensed an upset but little more than ten minutes later they were behind again.
Ikpeazu's head flick found Naismith, who nodded the ball over the Saints defence and into Lee's path. The midfielder let the ball bounce before lashing a left-footed effort home from six yards.
After Mitchell's exquisite overhead kick from a tight angle bounced off the crossbar, Naismith headed Hearts' third. A delivery into the St Mirren penalty box was not properly cleared and, after a couple of blocked attempts and ricochets, the Scotland internationalist nodded the ball out of Samson's reach and into the far corner.
To complete his hat-trick just three minutes later, Naismith collected Peter Haring's through ball and fired a low shot across Samson and into the net.
The visitors looked slightly punch-drunk but regrouped for the second half. McGinn forced the Hearts goalkeeper Zdenek Zlamal into his first noteworthy save shortly after the restart. John Souttar then cleared off his own goal line to deny Matthew Willock, who had dispossessed Garuccio 30 yards from goal.
Djoum entered the fray as Lee's replacement on 73 minutes to end a six-month injury absence. Wighton followed minutes later for his debut in maroon.
Although the game was well beyond St Mirren, they should have reduced the deficit ten minutes from the end. A cross ball was nodded down into the path of unmarked defender Alfie Jones six yards out, but he mishit his shot and allowed Zlamal to gather easily.
That pretty much summed up the afternoon for Alan Stubbs and his team. For Hearts, a strong start to the season is getting stronger.
Hearts (4-4-2): Zlamal; M Smith, Souttar, Dunne, Garuccio; Naismith, Haring, Lee (Djoum 73), Mitchell (Morrison 60); MacLean (Wighton 76), Ikpeazu. Unused subs: Doyle, Bozanic, Cochrane, Mulraney.
St Mirren (5-3-1-1): Samson; Hodson, Baird, Kpekawa, Jones, Coulson; Willock (Flynn 73), McGinn, Magennis; Smith (Mullen 79); Brock-Madsen. Unused subs: Muir, King, MacPherson, O'Keefe, Erhahon.
Referee: Kevin Clancy.