Mailys Mailagi starred alongside Grandhomme for Les Bleuettes, who backed up comprehensive victories over Wales and Scotland and fulfilled their tag as pre-tournament favourites.
England showed moments of brilliance but were undone by France’s physicality at the breakdown, ending the series with one win from three.
The visitors broke the deadlock when early pressure in England territory saw Mailagi bundle through two tackles, before Elina Folituu collected her offload and placed the ball down.
Soon Mailagi proved too hot to handle again, charging her way towards the tryline and flopping over right in front of the referee.
Grandhomme then rushed over in the corner to finish an excellent French move, before repeating the trick in identical fashion shortly afterwards for the visitors’ fourth try inside the opening 20 minutes.
England got off the mark 25 minutes in, grinding through the phases and earning a penalty try when France collapsed their driving maul, for which Mailagi saw yellow.
But in the blink of an eye, Aneymone Talalua raced past England’s scrambling line to restore France’s 18-point cushion.
Their sixth try came thanks to Iris Renaudin’s quick feet, which danced past England to give Grandhomme a clear run under the posts to complete the easiest of hat-trick chances. Renaudin converted the try for the first time in the game.
Mailagi’s return to the field spelled trouble for England, and soon she made the crucial metres that set up Anais Peralez’s dive under the posts to make the score 39-7 at half-time.
Les Bleuettes came out just as hungry after the break and Iness Zeze steamed through to dot down just two minutes into the second period.
Grace White stepped up to give the hosts something to cheer, evading French challenges and brutally fending off the final defender to cross in the corner for a super score.
But France immediately showed their team brilliance when Lylou Pedussaud charged onto two of her own kicks in the same run, before eventually a long cross-field kick was met perfectly by Grandhomme to touch down.
She then capitalised on a loose ball in England’s in-goal area to score her fifth try and push France beyond the 50-point mark. Zeze soon added her second after a long TMO delay.
With ten minutes left on the clock, the hosts converted their longest spell of possession into points when White finally found a gap around the French defence’s left flank.
But the visitors were soon back on the attack and Oihana Tome-Belmonte crashed over to bring France to 64 points, following another TMO review, before Alixe Valence provided a final flourish.