we find out who he is, sammy wallace. start doing a criminal background check and see if anyone is familiar with him. he has a pair of sunglasses on. he throws them on the ground. >> while negotiators engage wallace, zoe's mother is frantically pleading for her daughter. >> he wouldn't listen. he wouldn't put the knife down. i put my hands down and said in jesus name save my baby. please save my baby. >> she is agitating the situation because she is a loving mother. we had to force her from the scene for her protection and the protection of zoe. we wanted to negotiate it in to a peaceful end. her daughter is taken out of the store. wallace is increasingly erratic and exhibits signs of mental illness. >> he is talking about illuminoty which is a secret group that talks about conspiracy theories. he feels like the government is watching him and indicates that president george bush has been watching him. and he continues to ask us to call kevin, this dallas police officer. so we actually get ahold of kevin and kevin doesn't