// response is a string. After this line executes, obj is dynamic as expected
var obj = JsonConvert.DeserializeObject<dynamic>(response);
if (obj.Foo == "this works fine because obj is dynamic") {
   // Do whatever
}

// Again, response is a string. This time, obj ends up being an object, NOT dynamic
var obj = JsonConvert.DeserializeObject<dynamic>(response);
obj.Foo; // Fails because obj is an object
((dynamic)obj).Foo; // Works once I have type casted

// Every single method here returns an object and not dynamic as expected
dynamic obj2 = JsonConvert.DeserializeObject<dynamic>(response);
var obj3 = (dynamic)JsonConvert.DeserializeObject<dynamic>(response);
dynamic obj4 = (dynamic)JsonConvert.DeserializeObject<dynamic>(response);
dynamic obj5;
obj5 = (dynamic)JsonConvert.DeserializeObject<dynamic>(response);