I've got the standard task of referencing cells in other sheets from a
summary sheet using vlookup, no problems there.

The problem I have is that the sheet names to be indexed are listed in
a column in my summary sheet. I can't find a way to create the
vlookup formula referencing a cell to indicate the sheet name.

currently it works like this:
=VLOOKUP($C$4,'[BBC123.xls]Sheet1'!$E$16:$K$21,2,FALSE)

I want something like:
(cell C5 = BBC123.xls)
=VLOOKUP($C$4,'[ C5 ]Sheet1'!$E$16:$K$21,2,FALSE)

Ideas most welcome! TIA