SERIES Arrow Oliver (Stephen Amell) ask the Bratva for help in taking on Prometheus (Josh Segurra) — a move that leaves Diggle and Felicity (David Ramsey, Emily Bett Rickards) speechless. 8 p.m. KTLA The Goldbergs Barry (Troy Gentile) has big plans for Lainey (A.J. Michalka) on prom night. 8...