The appointment nets BLM a place on the AOL Time Warner media agency roster. The account was previously held by OMD UK.
BLM will initially plan and buy media for six launches in the pre-Christmas market. These include Tom Jones Live at Cardiff Castle and David Cassidy Live in Concert.
Warner Vision products released earlier this year include a Pop Idol video and Kylie Minogue and Madonna products.
Other projects that BLM will work on include the launch of Ministry of Sound, The Annual 2003 DVD and Ten Years Later with Jools Holland.
BLM's other wins this year include First Quench and Suzuki. However, it lost its flagship Blockbuster account to Walker Media.