Work visa after reaching hong kong

Can someone tell me?? Can I get work permit after reaching Hong Kong in tourist visa. Consultancy is offering a job  dey are asking to move as soon as possible. Dey are saying dey will arrange visa with in a week after reaching. Is it possible?? Someone tell help me

Yes it is technically possible, under two conditions:
1. you should not start working before the visa is issued
2. you need to exit HK and re-enter when you receive the visa (you can do that in a couple of hours just by taking a ferry to Macau and coming back)

This. Is it possible to obtain visa with in a week

Per the immigration website: "It normally takes four weeks to process visa/entry permit applications for employment upon receipt of all the required documents."