Why He'd Be a Good Pool Party Guest: No shirt? No shoes? No problem! / Why We May Have to Kick Him Out: There should only be one kind of hammock at a pool party, and it ain't a banana hammock.
Katy Perry as Katy Perry in 'Katy Perry: Part of Me'
Why She'd Be a Good Pool Party Guest: She's known for throwing some wild parties. ("Last Friday Night," anyone?) Plus, candy bikini! / Why We May Have to Kick Her Out: Indecisiveness. She's hot, then she's cold. Just get in the pool already!
Why He'd Be a Good Pool Party Guest: Skilled at aquatic-based activities, can call for pizza when it runs out. (See photo.) / Why We May Have to Kick Him Out: You sunk our inflatable battleship!
Why He'd Be a Good Pool Party Guest: Every pool party needs good music, so why not have live entertainment? / Why We May Have to Kick Him Out: We can only listen to Journey's "Don't Stop Believin'" so many more times.
Emma Stone as Gwen Stacy in 'The Amazing Spider-Man'
Why She'd Be a Good Pool Party Guest: Would bring some great summer reads, has hot gossip on Mary Jane. / Why We May Have to Kick Her Out: Refusal to squish any spiders that may wind up near the pool.
Why He'd Be a Good Pool Party Guest: Should any mutant killer piranhas find their way into the pool, he's the man to get them out. / Why We May Have to Kick Him Out: Brought along Gary Busey.
Why He'd Be a Good Pool Party Guest: Can get one helluva dance party started. Looks darn good in the water. (See photo.) / Why We May Have to Kick Him Out: Keeps hogging the pool ladder as part of his 'Step Up Revolution.'
Why He'd Be a Good Pool Party Guest: No party is ever truly complete without Cee Lo. Plus, he might bring Purrfect! / Why We May Have to Kick Him Out: Keeps spinning around in all the lounge chairs!
Why She'd Be a Good Pool Party Guest: Jessica Chastain is EVERYWHERE, including pool parties. / Why We May Have to Kick Her Out: Refusal to explain 'Tree of Life.'
Why He'd Be a Good Pool Party Guest: Transportation! If we run out of pool noodles, he can hop on his bike and pick up some more in no time. / Why We May Have to Kick Him Out: Keeps showing us all his gnarly scrapes and cuts from bike accidents.
Keira Knightley as Penny in 'Seeking a Friend for the End of the World'
Why She'd Be a Good Pool Party Guest: Poor girl is about to meet her doom. The least we can do is invite her over to our party. / Why We May Have to Kick Her Out: Goes on and on and on about the end of days. Yeesh! Way to kill the vibe!
Dwayne Johnson as Roadblock in 'GI Joe: Retaliation'
Why He'd Be a Good Pool Party Guest: Would make for a very efficient lifeguard. / Why We May Have to Kick Him Out: While at the grill incessantly asks guests if they can smell "What The Rock is cooking."
