COURTESY MGM

Lansbury in "All Fall Down"

Angela Lansbury distressed in "All Fall Down"

In the raucous and raunchy “Hot Tub Time Machine,” four slacker friends (John Cusack, Craig Robinson, Rob Corrdry, and Clark Duke) travel back in time in a hot tub and try to prevent their futures from changing. Though frequently crude, the film’s cast manages to deliver the comedic goods (and rear nudity).