So basically in my Fantasy WIP, a young temple acolyte is tasked with tracking down sacred objects and bring them back to her temple for them to be purified and quarantined. The empire sends two bodyguards to protect her. But they all have ulterior motives. The acolyte wants to use these relics to find her disappeared father while the bodyguards have been ordered to take the relics from her when gets all five in order for them be analyzed to help with the war effort. (The relics hold a special magic that the Temple wants under wraps)

I was wondering when would be best to bring this up to reveal this to the reader. Right away to get the tension going early on? In the middle when the readers has gotten to know them a bit more? Or near the end as a surprise?