Harris came in 28 balls into the innings with Spirit 40-2 and Griffith having already showing plenty of positive intent.
The 31-year-old, back with Spirit after a previous stint in 2023, soon joined in – clubbing Australia team-mate Amanda-Jade Wellington for six fourth ball.
She continued to attack Wellington but that almost proved her downfall as she offered a chance at long-off on 22 but the catch went down – an error duly punished by Harris.
The half-century came up from 28 balls – Spirit’s second quickest in The Hundred – and while Griffith fell the ball after matching that feat, Harris powered on.
Back-to-back sixes off Sophia Smale followed and Tash Farrant – who claimed two wickets on her return to the franchise tournament after injury ruled her out of the past three editions – received the same treatment.
Invincibles managed to keep her off strike late in the innings to deny Harris the chance of a century but her six sixes equalled the competition record for an individual innings and took Spirit to a formidable total.
For much of the chase it looked as though Spirit would defend the runs with ease but a magnificent knock from Lanning, assisted by Kapp, kept it interesting.
Even after Issy Wong bowled Kapp with a fine yorker, Lanning kept going and hit a series of towering sixes over the leg side.
But with seven balls remaining, the 33-year-old fell attempting to add her sixth maximum – England’s Wong again with the crucial wicket – and Spirit could breathe that bit easier as they saw out the game.
