I disagree with VP-F et al. If I am am out of currency for the 90 day rule, but otherwise correctly licensed, it would be perfectly correct for me to fly with another pilot, who was fully current, and for him to hand over control and allow me to make three landings as sole manipulator of the controls, thus regaining my currency. He remains PIC throughout and at no time am I PIC with a passenger whilst out of currency. Him handing over control to me does not make me PIC and him a passenger - he's the captain throughout, and to pre-empt the next argument, he does not need to be an instructor to hand over control to another person. I would record such a flight in my logbook as SNY, the times would not count towards any totals but my landings would count to requalify me.
Only if the other pilot is an examiner or instructor valid on type/class
I can be out on SEP 90 day rule as an instructor and still take a student up because they are counted as crew but couldn't take a pax in the back. its the same with night currency as well if you don't have an IR.
MJ whether or not you are an instructor is irrelevant, if you are out of 90 day currency you have to regain it before flying with anyone else on board except an examiner or instructor.