Once upon a time there was AT
Who combined with B to make BAT
But B ran away and C came to play and thus AT became CAT
C had an appointment to make, so F jumped into his place. So AT was FAT.
But F had a date with E.
(So ran away did he)
And H took his place. Now AT had a HAT
But T joined the party and thus HAT was THAT.
T and H decided to go to a ball and M joined to AT and AT became a MAT
Then G and N took over M's place and MAT became Pesky the GNAT.
Then G and N were replaced by P and all AT got was a PAT.
PAT came upon R and was dismayed to find that when AT joined R,
She was scared by a RAT
But S took over R's place and the RAT was been SAT
UPON! And SAT found V and S went into a VAT.
And when V ran away, that was all for AT.