Hmm what do you get with your regexp ?
I guess only the first row ?
Is the text in a file ?
If so, try to set $/=undef:

$/=undef;
$t=<FILEHANDLE>;
$t =~ s/^:::(.*):::/$1/;
print $t;
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This should work, if your memory if big enough to read the whole file in one $t.

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--the good, the bad and the physi--
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[download]