Task: Question Answering
Input (English): Passage: Ethan Hunt has retired from field work for the IMF. He instead trains new recruits while settling down with his fiancée, Julia Meade, a nurse who is unaware of Ethan's true job. He is approached by fellow IMF agent John Musgrave about a mission to rescue one of Ethan's protégés, Lindsey Farris. Lindsey was captured while investigating arms dealer Owen Davian. Musgrave has already prepared a team for Ethan: Declan Gormley, Zhen Lei, and his old partner Luther Stickell.
The team rescues Lindsey and collects two damaged laptop computers. As they flee, Ethan discovers an explosive pellet implanted in Lindsey's head. Before he can disable it, it goes off and kills her. Back in the U.S., Ethan and Musgrave are reprimanded by IMF Director Theodore Brassel. Ethan learns that Lindsey mailed him a postcard before her capture and discovers a magnetic microdot under the stamp.
IMF technician Benji Dunn recovers enough data from the laptops to determine Davian will be in Vatican City to obtain a mysterious object called the "Rabbit's Foot". Ethan plans a mission to capture Davian without seeking official approval. Before leaving, he and Julia have an impromptu wedding at the hospital's chapel. The team successfully infiltrates Vatican City and captures Davian.
On the flight back to the U.S., Ethan threatens to drop Davian from the plane as he interrogates him about the Rabbit's Foot, but Davian refuses to reveal anything. After landing, Ethan learns that the microdot contains a video of Lindsey warning that Brassel is working with Davian. The convoy taking Davian across the Chesapeake Bay Bridge–Tunnel is attacked, and Davian escapes. Realizing Julia is in danger, Ethan races to Julia's workplace, only to find she has already been kidnapped. Davian calls Ethan and gives him 48 hours to recover the Rabbit's Foot in exchange for Julia's life. But before Ethan can do anything, he is captured by the IMF. 
Question: What's the full name of who the hidden message on the postcard warn against?
Output (English): Theodore Brassel.