From publisher blurb:
You study the intricacies of battle between magic and weaponry. Your skills with weapons are legendary and mostly unrivaled but you use magic to enhance your battle prowess, using magic to get your enemies off-guard or striking from a range while you move closer to cut them down.
In Eldritch Warriors, you gain the Eldritch Warrior class archetype which grants your fighter spellcasting like a wizard. You can pick up magical feats which lets your fighter perform special magical actions in addition to their spellcasting. You can also find variants for different types of eldritch warriors such as Spirit Knights which get their spellcasting from spirits like animists or Victims of Fate which are cursed like a oracle.
You can also find the Eldritch Knight archetype which lets any class take on magical abilities, imbuing magical attacks into their Strikes.