How to access one class instance in editor script?

I have a script which gets FieldInfo from constructor arguments and store it within an Action class. I am trying to create instances of my own event class in inspector via reflection.

using UnityEngine; using System.Collections; using System.Reflection; using System.Collections.Generic;

[CustomEditor(typeof(EventScript))] public class EventScript : MonoBehaviour {

 public class Action
 {
     float time;
     List<FieldInfo> fieldInfos;
     List<object> fieldValues;
     
     public Action(float time, FieldInfo[] fieldInfos, string eventName)
     {
         this.time = time;
         this.fieldInfos = fieldInfos;
         this.fieldValues = new List<object>();
     }
 }
 
 public List<Action> actions;
 
 void CreateEvent()
 {
     // Call constructor of Event via reflection
 }

}

Then I try to get access to this List actions from Editor script and call a constructor with entered values;

using UnityEngine; using System.Collections; using UnityEditor; using System.Collections.Generic;

public class EventEditor : Editor {

 private List<EventScript.Action> actions;
 private EventScript currentEventScript;
 
 void OnEnable()
 {
     ...
 }
 
 void OnInspectorGUI()
 {
     // Fields for creating an instance of Event
     currentEventScript.CreateEvent(object[] arguments);
 }

}

How to get access to List "events" and current instance of EventScript from editor script? Or maybe there is a completely different approach?

I tried few different ways, but each time I've ended up with NullReferenceException.

The whole thing looks like these madskills below: different EventScripts contain different Actions and call constructors in different time.