Nick had done the same thing as Julian.
He had been working under Julian for decades, and he had seen this ability many times.
Julian just talked to somebody and mentioned specific things.
This triggered memories of these events, and Julian used his ability.
Julian would talk about his identity, and if the person already knew about it, their memories concerning his true identity would appear.
Metaphorically, it was like the person walked down a bridge towards a file with the memories, grabbed the file, and returned with it.
What Nick was doing was to let the person grab the file.
When they were walking back over the bridge, he was deleting the bridge behind them.
Lastly, he deleted the file in their hand.
The next moment, the person would be confused.
They knew that they had just grabbed a file, but there was no file.
This would make them search for the bridge again, but the bridge was gone.
