The membership barrier
The club rejects both pairs. Dennis and Dee expect preferential treatment.
Supporting source ↗CASE FILE · S06 E05
Mac and Charlie: White Trash
S06 E05Photograph not available
There's a heat wave in Philly, so Mac and Charlie decide to fix up an abandoned pool after they're denied admittance to a swim club. Meanwhile, Dennis and Dee try to beat the heat in a more "dignified" manner.
THE SHORT VERSION · SPOILERS AHEAD
INSIDE THE CASE.
Removing the exit
Mac and Charlie discard a filthy mattress, then realize it was their only escape from the pool.
Supporting source ↗A slippery afternoon
Frank introduces a greased watermelon at the public pool. Dennis and Dee struggle to maintain their superiority.
Supporting source ↗Pride before rescue
A pizza-delivery rescue fails. Charlie’s cut-off pocket then costs the stranded pair their phone.
Supporting source ↗THE EVIDENCE
THINGS IN THIS EPISODE.
Characters
Charlie Kelly180 other recorded episodes
Charlie sits on a battered chair at the bottom of the pool.Source ↗
Dee Reynolds179 other recorded episodes
Dee calls Charlie from a poolside lounge chair.Source ↗
Dennis Reynolds176 other recorded episodes
Dennis reacts to the conditions in the crowded public pool.Source ↗
Frank Reynolds171 other recorded episodes
Frank rejoins Dennis and Dee outside the private club.Source ↗
The pool pizza driverOnly recorded here so far
The delivery worker examines Mac’s offered chain.Source ↗
The swim-club attendantOnly recorded here so far
The attendant explains that the club cannot admit Mac and Charlie.Source ↗
Locations
Paddy’s Pub147 other recorded episodes
Mac unveils his proposed pool project at the bar.Source ↗
The abandoned diving poolOnly recorded here so far
Mac and Charlie stand beneath the delivery worker at the pool’s steep edge.Source ↗
The private swim clubOnly recorded here so far
Blue umbrellas and lounge chairs line the private pool behind reception.Source ↗
The public poolOnly recorded here so far
Dennis and Dee share the water with a crowd of swimmers.Source ↗
Objects
Bicycles8 other recorded episodes
A rusty bicycle lies among the rubbish inside the empty pool.Source ↗
Burner phonesOnly recorded here so far
Charlie reveals the phone he has had during their predicament.Source ↗
Fire hydrantsOnly recorded here so far
Frank operates a street hydrant after leaving the pools.Source ↗
MattressesOnly recorded here so far
The pair lift the filthy mattress over the edge.Source ↗
SkateboardsOnly recorded here so far
The pair include a skateboard in their memorial for Jamie Nelson.Source ↗
Food & drinks
Greased watermelonOnly recorded here so far
Frank introduces a greased-watermelon game at the public pool.Source ↗
Costumes
Cutoff shorts2 other recorded episodes
Charlie demonstrates the mobility of his very short denim cutoffs.Source ↗
Gold chainsOnly recorded here so far
Mac wears several gold-colored chains during the presentation.Source ↗
Miscellaneous
Funerals and memorials9 other recorded episodes
Mac and Charlie join hands beside their improvised memorial.Source ↗
FOLLOW THE THREAD
CONNECTED EPISODES.
S04 E12 Connected through Cutoff shorts, Paddy’s Pub, Frank Reynolds and 4 more.
S05 E07 
Connected through Cutoff shorts, Paddy’s Pub, Frank Reynolds and 4 more.
S04 E04 Connected through Pizza, Bicycles, Paddy’s Pub and 3 more.
S01 E06 Connected through Hoses, Funerals and memorials, Paddy’s Pub and 4 more.
SOURCES & NOTES.
Tags document researched occurrences, not every appearance. Read the research notes and attribution.