The former England Under-20s ace has joined the black, green and gold on trial and will start at seven against the British Army in Wednesday night's Mobbs Memorial Match at cinch Stadium at Franklin's Gardens.
Hinkley has had a tough time of things due to injuries, hampering his progress after he swapped Gloucester for Exeter Chiefs back in 2020.
But the 23-year-old's pedigree is clear for all to see.
And he will now get a chance to prove himself at Saints.
"Aaron didn't get the rub of the green at Exeter and had a tough bit of time there but he's come to us and we've got fresh eyes on him," said Saints attack coach Sam Vesty.
"He's been really impressive on the training field and we're looking forward to seeing him in the Mobbs game."
Saints skipper Ludlam plays in the same position as Hinkley and has already been impressed with his work ethic in training.
"Aaron's been really good," Ludlam said.
"It's hard to see a massive amount of him because he hasn't had a great opportunity to go and put what you do in training on the pitch.
"But he's come in, he's worked really hard, you can tell he's a really skilful player, loads of natural talent and I'm really excited about where he's going to go over the next year or so."