For children adopted by families in foreign lands, the prospect of tracing a remote cultural heritage can prove a complicated venture with unforeseen consequences. Such is the situation encountered by the titular characters in playwright Mat Smart’s poignant piece, Samuel J. & K., two brothers brought together when three-year-old Samuel K. was adopted from his Cameroon homeland into Samuel J.’s white American family. When Samuel K. graduates from college, the matter of ancestry manifests in the form of an unwanted gift from his older brother: two roundtrip plane tickets to Cameroon. Smart’s provocative script reveals the latent personal and social fissures in their relationship, fractures deep enough to jeopardize the foundations of their familial connection. Receiving its local premiere at Gremlin Theatre, this Brian Balcom-directed staging features Paul LaNave and Wariboko Semenitari as the two brothers who test the strained resiliency of a frayed lifelong bond.