A three-man play opened this week in central Iowa which promoters say has been so popular elsewhere, it could end up being booked in Des Moines for months, or even years. The comedy “Triple Espresso” has already been playing in Minneapolis for more than 120 weeks. Executive producer Dennis Babcock says it’s next to impossible to explain the show’s plot.The show is playing in four cities worldwide now — Des Moines, Minneapolis, San Diego and Dublin, Ireland. Babcock says the comedy is appropriate for grandparents, kids as young as six and anyone in between. Babcock, who has Iowa roots, says the comedy involves three old friends — a magician, a piano player and a comedian.The son of an Air Force officer, Babcock went to high school in Sioux City, graduated from Iowa State University in 1970, and taught drama at Urbandale High School in the early ’70s. Though he now lives in Minneapolis, Babcock says it’s a personal triumph for him to return to Des Moines with this show as the exec-producer.The play is being performed in the Temple for the Performing Arts (the former Masonic Temple) in Des Moines. Tickets are available through the Civic Center of Greater Des Moines.