The new parents are going to guest star on an upcoming episode of "CSI: NY," People reports.
According to a source, "Ashlee will be playing Lia Wickfield and Pete will be playing Chester Bryon. They are a Bonnie and Clyde-like couple."
Simpson-Wentz had already begun filming on Friday, Jan. 16, while Wentz will join her on set sometime this week.
The "CSI" franchise has been a draw for guest stars, particularly those of the musical persuasion. Lest we forget, Nelly and Kevin Federline have both guest starred, and CBS announced last week that country music sensation Taylor Swift will take a turn on the flagship show.
Simpson-Wentz already has a creditable acting resume having appeared on "7th Heaven" and on the big screen in "Undiscovered."