Northamptonshire 71 for 8 (Henry 6-31) trail Kent 137 (Gleeson 3-16, Buck 3-28) by 66 runs
Kent pace bowler Matt Henry bagged 6 for 31 to leave Northamptonshire reeling on 71 for 8 when bad light and rain ended prematurely an action-packed opening day of Specsavers County Championship action.
On a thrilling day when 18 wickets fell, Henry - the New Zealand Test paceman - took his season's red-ball wicket tally to 56 as the Division 2 promotion hopefuls recovered from a poor batting display to leave the visitors punch drunk and still 66 runs in arrears by the time the umpires stopped the contest and took the sides off for bad light just before 5pm.
Northamptonshire, who started their first innings response at 2.42pm, struggled to cope with the guile of Darren Stevens and the pace of Henry, the Championship's leading wicket-taker.
Henry, who went into the game with 50 scalps to his name at an average of 15.84, forced Ben Curran to play on to leg stump and then plucked out the middle and off stumps of Ricardo Vasconcelos after rushing one through the South African left-hander's gate.
Stevens snared Luke Proctor leg before with an in-swinger, Henry re-arranged Alex Wakely's poles with a yorker and then Richard Levi scooped a rearing delivery from Henry to square leg to send the visitors in at tea on 31 for 5.
Three overs after tea, Saif Zaib feathered an attempted leg-glance against Stevens through to the keeper then, three balls later, Henry sent Nathan Buck's off stump cartwheeling to secure his fifth five-wicket return of the summer.
Northamptonshire limped past their lowest ever score against Kent - 39 all out at Wantage Road in 1907 - but with their score on 44 Adam Rossington's top edged pull against Henry skied to long leg.
Henry gave way after 12-overs as did Stevens, with 2 for 26, allowing Brett Hutton and Richard Gleeson to add a precious 27 before the players went off for bad light.Batting first after an uncontested toss, Kent's top-order were soon in trouble against the new ball and under leaden skies and had lost both openers within five overs.
Zak Crawley, fending down the line of off stump, feathered a Hutton away-swinger through to the keeper, then, seven balls later, Sean Dickson went back and across his stumps to miss an off-cutter from Ben Sanderson and depart leg before.
Experienced third-wicket partners Joe Denly and Heino Kuhn took advantage of the short St Lawrence boundaries to keep the board ticking over at a decent rate and raise the home 50 after 15 overs. But, with his score on 16, Kuhn played around a full, in-swinger from Buck to also go lbw.
Having batted 76 minutes for his 14, Denly's late decision to withdraw the bat outside off stump against Gleeson proved fatal as the ball glanced off the bat face and through to the keeper.
Batting under floodlights after lunch, Kent's position quickly became gloomier as they lost their last six wickets for 46 runs inside 18 overs.
Sam Billings nicked off against Gleeson, Stevens prodded at Sanderson to become the third leg before victim and, having scratched around for 98 minutes for 23, Daniel Bell-Drummond edged behind.
Sanderson ran one in off the seam to peg back Grant Stewart's off stump, then Buck polished the job off with two wickets in as many balls. Henry heaved across the line to lose off stump then Ivan Thomas was caught on the crease and palpably leg before as Kent succumbed inside 47 overs with Gleeson, Sanderson and Buck claiming three wickets apiece.
Gleeson suggested the pitch was nothing out of the ordinary.
"To bowl them out for 137 you think 'great start' but they bowled tremendously in helpful conditions," he said. "It's not really brightened up all day, it's stayed overcast and the wicket has been doing a little bit throughout.
"When we turned up we felt the wicket looked quite flat and that we were in for a long toil, but it doesn't look that way from the scoreboard. The pitch has done a little bit, but nothing out of the ordinary. They were just very tough overhead conditions all day."