A reclusive mathematical genius must abandon the only world she knows to flee cross-country with the mysterious stranger who has just killed her formidable would-be assassin with his bare hands.

The order of the descriptions is confusing, I’ll try and rearrange them:

After escaping an attempted murder, with the help of a mysterious stranger, a reclusive mathematical genius must flee across the country.

The problem is that there is no logical reason for her to flee, why must she go on the run?

Could it be that she worked for the government and she fears they will send another killer? Whatever the reason it needs to be mentioned in the logline, as the cause and effect relationship between the events of the story is unclear.

Secondly, to what end? What is she trying to achieve by going on the run? What is her goal?