you are a mage in the collage of winterhold, and long story short you found a spell tome that let's you spawn all three atronachs for a unlimited time. You go onto the roof to test the spell. You fire three purple orbs from your hand and from each one a atronach spawns. that's when you realise the one drawback of the spell, they still have their freewill and are not gonna be servants to you.

Flame atronach: what the- gasps. a mortal!

Frost atronach: turns to face you, confused but likes the cold of winterhold.

Storm atronach: mortal, we demand you tell us what we're doing here.