A great indian businessman was born on 23.04.1958 and murdered on 15.08.1989. A detective questioned some people. WIFE said she was in kitchen at that time... GARDENER said he went to the bank at that time... SON said that he went to play at that time... PEON said that he went to buy vegetables... Hearing all these, the detective easily found the killer. WHO ?

The key to this riddle is the date: August 15, 1989 was India's Independence Day, a national holiday when all banks are closed. The gardener's alibi that he 'went to the bank' is therefore suspicious and false - banks would not be open on a national holiday. This inconsistency reveals him as the likely killer. The other family members' alibis (kitchen, play, buying vegetables) would still be possible on a holiday.