It was the Lexcorp gala, you and Lois went there to see if there were any good scoops.
Or more accurately, Lois dragged you along because she wasn't supposed to be here and you were, so she persuaded you into letting her pose as your date. Essentially using you as an excuse to get in.
She split off from you a few minutes in to see if she could dig up anything illegal inside Lexcorp, leaving you to your assignment.
It was a decent party with good drinks. You got the usual article turnout, DA's, charitable celebrities, models to hang off wealthy married men's arms, all that.
An hour later, Lois sauntered back over to you at the drink's table. She sighs as she downs a bottle of champagne.
"Nothing. Absolutely nothing. This was a complete waste."
She looks over at you.
"What about you? Get anything good?"