What to read after Rip Tide?

When pirates attack a cargo ship off the Somalian coast and one of them is found to be a British-born Pakistani, alarm bells start ringing at London's Thames House. MI5 Intelligence Officer Liz Carlyle is brought in to establish how and why a young British Muslim could go missing from his well-to-do family in Birmingham and end up on board a pirate skiff in the Indian Ocean, armed with a Kalashnikov.

Meanwhile, the owner of the charitable NGO that leased the ship suspects that his fleet is being deliberately targeted. But why would pirates be interested in charitable supplies? And how do they know the exact details of his ships' cargo and routes?
When an undercover operative connected to the case turns up dead in Athens it looks like piracy may be the least of the Service's problems.

Now Liz, with the help of Peggy Kinsolving, Dave Armstrong, and the rest of her unit, attempts to unravel the connections between Pakistan, Greece and Somalia. She'll have to rely on their wits--and the judicious use of force--to get to the truth. And she doesn't have long, as trouble is brewing closer to home: the kind of explosive trouble that MI5 could do without.