Ax 2012 custom look up

I want to create look up of 3 tables and their fields , my requirement is in the first field i would like to show the 3 table names as look up and in the second field i would be showing all the fields of the table selected in the first field.

For e.g if i have Route, sales basket and Invent table in look up of first field, i select Invent table in the first field then in the second field i have to show all the fields of invent table as look up. please help me in this regard.

I have tried using the normal process for look up but could not succeed, please help me in finding the right direction

can you tell us, where you are going to have information tables??