Ragtag Rescue

Lancelot and Mr. Biggs face a traitor, an intruder, and an imposter in this second book in the Lancelot Maddox series.
There's a traitor at the intelligence agency. Lancelot and Mr. Biggs must discover who the traitor is before classified information falls into the hands of foreign agents.
An intruder hides explosives at various places in the intelligence agency. Lancelot and Mr. Biggs must locate the intruder and the explosives before it's too late.
Mr. Biggs' life is threatened by an imposter delivering toxic material disguised as regular mail. When the imposter kidnaps Lancelot, Mr. Biggs uses all his resources to save the young decoder's life.