The title literally means Heaven, it's my Tuesday! but is also a wordplay on the more common Ciel, mon mari! expression, which means Heaven, it's my husband! (coming back home while I am busy with another man).
Dechavanne invited groups of people who hated each other in real life and let them "discuss" their differences. For example he invited priests and homosexuals, Jewish groups and neo-Nazis, etc.
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