Shut the f*ck outta here
It is the combination of "Shut the f*ck up" and "Get the f*ck outta here." It is used to express extreme surprise or disbelief.
Dave: I've been having sex with my 40yr old boss for months now, and she just told me she's pregnant
Smitha: Shut the f*ck outta here, are you serious?!
Smitha: Shut the f*ck outta here, are you serious?!