An Epic (yet dorky) Search (to steal) Fo(u)r Comics
As cool and awesome as the title may be... a little misleading for your story.
Basically, your friend is a huuuuge fan of the superhero, Toxic Hatchet, and his little sidekick: Crybot. Upon hearing about this, you mention that your mother is also a huge fan. You're not sure how you were convinced to steal not just her classic comics of the hero... but the four rarest ones she owns. The most important part, is that it has now become your mission to sneak in (ahem, unlock the door with the key you've had since you were ten), steal the comics (obviously borrow them... your friend had no intention of keeping them), and getting out safe and sound (well... I highly doubt your mom would do anything so rash as to stab you if you got caught).
On top of that, you're sure she once owned an ultra rare comic that you have never been allowed to touch... but you can't for the life of you remember where she may have put it. Or any of the comics, for the matter.
To be brutally honest, you're not even sure if your key still works.