From the moment Chip Rohrbach saunters on to the Pennsylvania Playhouse stage as Nicely Nicely Johnson and begins to sign ''Fugue for Tinhorns,'' it's clear that this ''Guys and Dolls'' is going to be a sure bet.

Rohrbach, who plays Johnson with a roguish, boyish charm, and Jim Tully as Ben Southstreet, Johnson's fellow small-time gambler, show a delightful familiarity, playing up their characters' idiosyncrasies through over-the-top gesturing, vaudevillesque facial expressions and broad comic physical interaction. All these gimmicks work in spades. And to add to the pot, Rohrbach's powerful voice.

And when it comes to winning hearts, director Beth Breiner has scored again with her casting of Ted Rewak as Sky Masterson and Kate Varley as Sarah Brown. They have beautiful voices that soar and thrill.

Like Rohrbach and Tully, they are stage pros, not afraid to embellish their characters with wonderful details. Varley is particularly enchanting in the Havana nightclub scene as she becomes more and more inebriated. She stumbles and wobbles all over the stage as she falls more and more in love with Rewak.

Lori Sivick not only captures the accent of Miss Adelaide, but also grasps the character's challenged reality. Coquettish and naïve, Sivick is alternately delightful and soulful as she sings ''Adelaide's Lament,'' and she becomes an energized female warrior in ''Marry the Man Today,'' her duet with Varley.

Mark Breiner's Nathan Detroit is a harried and inept schmiel who is assertive with his runners, but an officious yes-man when challenged by authority.

Gary Boyer's Harry the Horse, another unique Damon Runyon gambler, is as much fun to watch as he battles with Nicely Nicely and Benny. He is the subservient tool of the overpowering Big Jule, who is played by Gary Martin as a man of few words, but obvious intentions.

Don Swan as Arvide, the Mission General, wields his oversized drum with energy and determination. He reveals a softer, more tender side in his solo, ''More I Can Not Wish You,'' as Sarah's surprisingly worldly grandfather.

Among the many standout musical numbers are Rewak and Varley singing ''I'll Know,'' Varley's ''If I Were a Bell,'' Rewak's ''My Time of Day,'' Rohrbach and Tully's ''Guys and Dolls,'' and the ensemble number, ''Sit Down, You're Rockin' the Boat.''

Breiner has a gift for good pacing and visually interesting staging. Actors come and go, adding a freshness and joie de vivre. Scene changes are done quickly, smoothly and inventively.

Rohrbach also served as set designer and his colorful painted backdrop of the New York skyline seems to glow in full light and create romantic settings when the lights are dimmed. His moveable flats keep the action moving from Broadway to the Save a Soul Mission to a nightclub in Havana and then to the finale in the gamblers' gambling den.

Myra Yellin Outwater is a freelance writer.