quicker

Extremely quickly; almost immediately; suddenly or in a very short space of time. Once I'm finished with high school, I'll be outta this two-bit town quicker than you can say Jack Robinson! I was out fishing one day when, quicker than you can say Jack Robinson, a 20-pound trout jumped out of the water and right into my lap!

Fig. almost immediately. (Often found in children's stories.) And before you could say Jack Robinson, the bird flew away. I'll catch a plane and be there quicker than you can say Jack Robinson.

Inf. very fast. You got over here quicker than hell. Be careful in the stock market. You can lose all your money quicker than hell.

Also, quicker than you can say Jack Robinson. Almost immediately, very soon, as in I'll finish this book before you can say Jack Robinson. This expression originated in the 1700s, but the identity of Jack Robinson has been lost. Grose's Classical Dictionary (1785) said he was a man who paid such brief visits to acquaintances that there was scarcely time to announce his arrival before he had departed, but it gives no further documentation. A newer version is before you know it, meaning so soon that you don't have time to become aware of it (as in He'll be gone before you know it).