From Samuel French:

The smash comedy hit of the London and Broadway stages, this much-revived classic from the playwright of Private Lives offers up fussy, cantakerous novelist Charles Condomine, re-married but haunted (literally) by the ghost of his late first wife, the clever and insistent Elvira who is called up by a visiting "happy medium", one Madame Arcati. As the (worldly and un-) personalities clash, Charles' current wife Ruth is accidentally killed, "passes over", joins Elvira and the two "blithe spirits" haunt the hapless Charles into perpetuity.