After his discharge, Arnold returned to Baltimore and in the late summer of 1864, he was recruited by Booth to be part of the kidnap plot. Bored and unemployed, Arnold accepted. On March 15, 1865, the conspirators met at Gautier's Restaurant on
Pennsylvania Avenue to discuss the plot. Arnold and the other alleged conspirators,
John Wilkes Booth,
David Herold,
Lewis Powell,
Michael O'Laughlen, and
John Surratt, were to kidnap Lincoln, ferry him through
Van Ness Mansion owned by
Thomas Greene, and hold him to exchange for the Confederate prisoners in
Washington D.C. This was attempted twice but failed because Lincoln was not where they thought he would be. After the failure, Arnold took a clerk's job in
Old Point Comfort, Virginia. == Arrest and trial ==