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We propose to study the last HST-accessible white dwarf (WD) cooling sequence (CS) for a nearby globular cluster (GC) comma the chemically complex comma extreme blue horizontal branch cluster NGC 6752. Over 97% of stars end their lives as WDs comma and the WD CS provides constraints not only on the age comma but also potentially the star formation history of a GC. The CS of WDs also lies in the least-explored region of the color-magnitude diagram of old stellar populations. Recent deep imaging with HST has successfully reached the end of the WD CS in only three d_commaclassicald_comma old GCs comma M4 comma NGC 6397 and 47 Tuc comma and reveals an unexpectedly complex comma and double-peaked comma WD CS in the metal rich old open cluster NGC 6791. One more investigation is in progress on the massive globular Omega Centauri comma where over 14 sub-populations are known to exist. While almost every cluster is known to host multiple populations comma every single cluster is unique. NGC 6752 is a bridge between the relatively simple globular clusters comma and Omega Cen comma the most complex globular cluster known. NGC 6752 has an extended blue horizontal branch comma a collapsed core and 3 chemically distinct populations. It is our last chance to add diversity to our very limited sample of WD CS comma so far containing only 3 globular clusters comma one old open cluster comma and the complex Omega Cen system. We need to undertake this investigation while HST is still operational comma as there is no foreseeable opportunity in the post-HST era to have one extra WD CS in the homogeneus optical photometric system of HST.