An irresistible mystery
Mac and Dennis abandon Dee’s evening plans to investigate repeated messes in Charlie and Frank’s bed.
Supporting source ↗CASE FILE · S04 E07

Frank and Charlie find that someone has soiled their bed, and Mac and Dennis join them as they attempt to catch the culprit. Meanwhile, Dee leads Artemis and the waitress on a "Sex and the City"-style night on the town.
THE SHORT VERSION · SPOILERS AHEAD
Mac and Dennis abandon Dee’s evening plans to investigate repeated messes in Charlie and Frank’s bed.
Supporting source ↗The person willing to examine the sample is an economics student; the gang mistakes enthusiasm for scientific expertise.
Supporting source ↗Dee recruits Artemis and the Waitress, but drinks, expensive shoes and an art-gallery visit fail to deliver her sophisticated evening.
Supporting source ↗Artemis offers elaborate reconstructions, shown as imagined scenes. Frank interrupts to claim responsibility for every incident because he finds it funny.
Supporting source ↗THE EVIDENCE
Charlie demonstrates the sleeping arrangement on the shared bed.Source ↗
Dee tries on shoes during her shopping trip.Source ↗
Dennis uses a flashlight during the overnight observation.Source ↗
Frank joins Charlie in the bed demonstration.Source ↗
The student examines the evidence under a bright task lamp.Source ↗
The Waitress joins Dee and Artemis at the martini bar.Source ↗
Dee visits a gallery after leaving the others.Source ↗
A neon Bleu Martini sign identifies the evening venue.Source ↗
The disputed bed belongs to Charlie and Frank.Source ↗
The pub becomes the setting for the final reconstruction.Source ↗
Dee tries on heels in a shop lined with shoe displays.Source ↗
A wall of photographs, papers and red string accompanies Artemis’s presentation.Source ↗
The observers illuminate the bed at night.Source ↗
Dee struggles into a pair of dress shoes.Source ↗
Dee holds Charlie’s notebook while negotiating with the Waitress.Source ↗
Dee orders Cosmos for the group despite the Waitress’s objection.Source ↗
Dee withholds the notebook to secure the Waitress’s company.Source ↗
Artemis presents competing theories before Frank confesses.Source ↗
Tags document researched occurrences, not every appearance. Read the research notes and attribution.