NCIS: Los Angeles: Collateral

A millionaire former CIA man meets a premature end when someone plants a controlled explosive in his lighter. Over the years he had built up an impressive list of enemies, so finding his killer looks like an uphill task, but as the agents start working through the potential culprits, a recovered computer file leads them to an escort service used by a wanted hitman. However, what they don't bank on is the chief suspect turning up dead