diff --git a/ProjectPlugins/CodexPlugin/OverwatchSupport/ModelExtensions.cs b/ProjectPlugins/CodexPlugin/OverwatchSupport/ModelExtensions.cs
new file mode 100644
index 00000000..7b3bd638
--- /dev/null
+++ b/ProjectPlugins/CodexPlugin/OverwatchSupport/ModelExtensions.cs
@@ -0,0 +1,72 @@
+namespace OverwatchTranscript
+{
+    [Serializable]
+    public partial class OverwatchHeader
+    {
+        public OverwatchCodexHeader? CodexHeader { get; set; }
+    }
+
+    [Serializable]
+    public partial class OverwatchEvent
+    {
+        public OverwatchCodexEvent? CodexEvent { get; set; }
+    }
+
+    [Serializable]
+    public class OverwatchCodexHeader
+    {
+        public int TotalNumberOfNodes { get; set; }
+    }
+
+    [Serializable]
+    public class OverwatchCodexEvent
+    {
+        public NodeStartedEvent? NodeStarted { get; set; }
+        public NodeStoppedEvent? NodeStopped { get; set; }
+        public FileUploadedEvent? FileUploaded { get; set; }
+        public FileDownloadedEvent? FileDownloaded { get; set; }
+        public BlockReceivedEvent? BlockReceived { get; set; }
+    }
+
+    #region Scenario Generated Events
+
+    [Serializable]
+    public class NodeStartedEvent
+    {
+        public string Name { get; set; } = string.Empty;
+        public string Image { get; set; } = string.Empty;
+        public string Args { get; set; } = string.Empty;
+    }
+
+    [Serializable]
+    public class NodeStoppedEvent
+    {
+        public string Name { get; set; } = string.Empty;
+    }
+
+    [Serializable]
+    public class FileUploadedEvent
+    {
+        public ulong ByteSize { get; set; }
+        public string Cid { get; set; } = string.Empty;
+    }
+
+    [Serializable]
+    public class FileDownloadedEvent
+    {
+        public string Cid { get; set; } = string.Empty;
+    }
+
+    #endregion
+
+    #region Codex Generated Events
+
+    [Serializable]
+    public class BlockReceivedEvent
+    {
+        public string BlockAddress { get; set; } = string.Empty;
+        public string PeerId { get; set; } = string.Empty;
+    }
+
+    #endregion
+}
diff --git a/Tests/FrameworkTests/FrameworkTests.csproj b/Tests/FrameworkTests/FrameworkTests.csproj
index 4bc09aa5..cceced4b 100644
--- a/Tests/FrameworkTests/FrameworkTests.csproj
+++ b/Tests/FrameworkTests/FrameworkTests.csproj
@@ -17,6 +17,7 @@
     <ProjectReference Include="..\..\Framework\NethereumWorkflow\NethereumWorkflow.csproj" />
     <ProjectReference Include="..\..\Framework\Utils\Utils.csproj" />
     <ProjectReference Include="..\..\ProjectPlugins\CodexContractsPlugin\CodexContractsPlugin.csproj" />
+    <ProjectReference Include="..\..\Tools\OverwatchTranscript\OverwatchTranscript.csproj" />
   </ItemGroup>
 
 </Project>
diff --git a/Tests/FrameworkTests/OverwatchTranscript/TranscriptTests.cs b/Tests/FrameworkTests/OverwatchTranscript/TranscriptTests.cs
new file mode 100644
index 00000000..b88d3325
--- /dev/null
+++ b/Tests/FrameworkTests/OverwatchTranscript/TranscriptTests.cs
@@ -0,0 +1,103 @@
+using Newtonsoft.Json;
+using NUnit.Framework;
+using OverwatchTranscript;
+
+namespace FrameworkTests.OverwatchTranscript
+{
+    [TestFixture]
+    public class TranscriptTests
+    {
+        private const string TranscriptFilename = "testtranscript.json";
+        private const string HeaderKey = "testHeader";
+        private const string HeaderData = "abcdef";
+        private const string EventData0 = "12345";
+        private const string EventData1 = "678";
+        private const string EventData2 = "90";
+        private readonly DateTime t0 = DateTime.UtcNow;
+        private readonly DateTime t1 = DateTime.UtcNow.AddMinutes(1);
+        private readonly DateTime t2 = DateTime.UtcNow.AddMinutes(2);
+
+        [Test]
+        public void WriteAndRun()
+        {
+            var workdir = Path.Combine(Path.GetTempPath(), Guid.NewGuid().ToString());
+
+            WriteTranscript(workdir);
+            ReadTranscript(workdir);
+
+            File.Delete(TranscriptFilename);
+        }
+
+        private void WriteTranscript(string workdir)
+        {
+            var writer = new TranscriptWriter(workdir);
+
+            writer.AddHeader(HeaderKey, new TestHeader
+            {
+                HeaderData = HeaderData
+            });
+
+            writer.Add(t0, new MyEvent
+            {
+                EventData = EventData0
+            });
+            writer.Add(t2, new MyEvent
+            {
+                EventData = EventData2
+            });
+            writer.Add(t1, new MyEvent
+            {
+                EventData = EventData1
+            });
+
+            writer.Write(TranscriptFilename);
+        }
+
+        private void ReadTranscript(string workdir)
+        {
+            var reader = new TranscriptReader(workdir, TranscriptFilename);
+
+            var header = reader.GetHeader<TestHeader>(HeaderKey);
+            Assert.That(header.HeaderData, Is.EqualTo(HeaderData));
+
+            var events = new List<MyEvent>();
+            reader.AddHandler<MyEvent>((utc, e) =>
+            {
+                e.CheckUtc = utc;
+                events.Add(e);
+            });
+
+            Assert.That(events.Count, Is.EqualTo(0));
+            reader.Next();
+            Assert.That(events.Count, Is.EqualTo(1));
+            reader.Next();
+            Assert.That(events.Count, Is.EqualTo(2));
+            reader.Next();
+            Assert.That(events.Count, Is.EqualTo(3));
+            reader.Next();
+            Assert.That(events.Count, Is.EqualTo(3));
+
+            Assert.That(events[0].CheckUtc, Is.EqualTo(t0));
+            Assert.That(events[0].EventData, Is.EqualTo(EventData0));
+            Assert.That(events[1].CheckUtc, Is.EqualTo(t1));
+            Assert.That(events[1].EventData, Is.EqualTo(EventData1));
+            Assert.That(events[2].CheckUtc, Is.EqualTo(t2));
+            Assert.That(events[2].EventData, Is.EqualTo(EventData2));
+
+            reader.Close();
+        }
+    }
+
+    public class TestHeader
+    {
+        public string HeaderData { get; set; } = string.Empty;
+    }
+
+    public class MyEvent
+    {
+        public string EventData { get; set; } = string.Empty;
+
+        [JsonIgnore]
+        public DateTime CheckUtc { get; set; }   
+    }
+}
diff --git a/Tools/OverwatchTranscript/Model.cs b/Tools/OverwatchTranscript/Model.cs
index 0069c4b8..7130cc22 100644
--- a/Tools/OverwatchTranscript/Model.cs
+++ b/Tools/OverwatchTranscript/Model.cs
@@ -1,76 +1,30 @@
 namespace OverwatchTranscript
 {
     [Serializable]
-    public class Transcript
+    public class OverwatchTranscript
     {
-        public Header Header { get; set; } = new();
-        public Event[] Events { get; set; } = Array.Empty<Event>();
+        public OverwatchHeader Header { get; set; } = new();
+        public OverwatchEvent[] Events { get; set; } = Array.Empty<OverwatchEvent>();
     }
 
     [Serializable]
-    public class Header
+    public class OverwatchHeader
     {
-        public int TotalNumberOfNodes { get; set; }
+        public OverwatchHeaderEntry[] Entries { get; set; } = Array.Empty<OverwatchHeaderEntry>();
     }
 
     [Serializable]
-    public class Event
+    public class OverwatchHeaderEntry
+    {
+        public string Key { get; set; } = string.Empty;
+        public string Value { get; set; } = string.Empty;
+    }
+
+    [Serializable]
+    public class OverwatchEvent
     {
         public DateTime Utc { get; set; }
-        public ScenarioFinishedEvent? ScenarioFinished { get; set; }
-        public NodeStartedEvent? NodeStarted { get; set; }
-        public NodeStoppedEvent? NodeStopped { get; set; }
-        public FileUploadedEvent? FileUploaded { get; set; }
-        public FileDownloadedEvent? FileDownloaded { get; set; }
-        public BlockReceivedEvent? BlockReceived { get; set; }
+        public string Type { get; set; } = string.Empty;
+        public string Payload { get; set; } = string.Empty;
     }
-
-    #region Scenario Generated Events
-
-    [Serializable]
-    public class ScenarioFinishedEvent
-    {
-        public bool Success { get; set; }
-        public string Result { get; set; } = string.Empty;
-    }
-
-    [Serializable]
-    public class NodeStartedEvent
-    {
-        public string Name { get; set; } = string.Empty;
-        public string Image { get; set; } = string.Empty;
-        public string Args { get; set; } = string.Empty;
-    }
-
-    [Serializable]
-    public class NodeStoppedEvent
-    {
-        public string Name { get; set; } = string.Empty;
-    }
-
-    [Serializable]
-    public class FileUploadedEvent
-    {
-        public ulong ByteSize { get; set; }
-        public string Cid { get; set; } = string.Empty;
-    }
-
-    [Serializable]
-    public class FileDownloadedEvent
-    {
-        public string Cid { get; set; } = string.Empty;
-    }
-
-    #endregion
-
-    #region Codex Generated Events
-
-    [Serializable]
-    public class BlockReceivedEvent
-    {
-        public string BlockAddress { get; set; } = string.Empty;
-        public string PeerId { get; set; } = string.Empty;
-    }
-
-    #endregion
-}
\ No newline at end of file
+}
diff --git a/Tools/OverwatchTranscript/OverwatchTranscript.csproj b/Tools/OverwatchTranscript/OverwatchTranscript.csproj
index cfadb03d..51eb283c 100644
--- a/Tools/OverwatchTranscript/OverwatchTranscript.csproj
+++ b/Tools/OverwatchTranscript/OverwatchTranscript.csproj
@@ -6,4 +6,8 @@
     <Nullable>enable</Nullable>
   </PropertyGroup>
 
+  <ItemGroup>
+    <PackageReference Include="Newtonsoft.Json" Version="13.0.3" />
+  </ItemGroup>
+
 </Project>
diff --git a/Tools/OverwatchTranscript/TranscriptConstants.cs b/Tools/OverwatchTranscript/TranscriptConstants.cs
new file mode 100644
index 00000000..245fe492
--- /dev/null
+++ b/Tools/OverwatchTranscript/TranscriptConstants.cs
@@ -0,0 +1,8 @@
+namespace OverwatchTranscript
+{
+    public static class TranscriptConstants
+    {
+        public const string TranscriptFilename = "transcript.json";
+        public const string ArtifactFolderName = "artifacts";
+    }
+}
diff --git a/Tools/OverwatchTranscript/TranscriptReader.cs b/Tools/OverwatchTranscript/TranscriptReader.cs
new file mode 100644
index 00000000..2fbb1a78
--- /dev/null
+++ b/Tools/OverwatchTranscript/TranscriptReader.cs
@@ -0,0 +1,92 @@
+using Newtonsoft.Json;
+using System.IO.Compression;
+
+namespace OverwatchTranscript
+{
+    public class TranscriptReader
+    {
+        private readonly string transcriptFile;
+        private readonly string artifactsFolder;
+        private readonly Dictionary<string, Action<DateTime, string>> handlers = new Dictionary<string, Action<DateTime, string>>();
+        private readonly string workingDir;
+        private OverwatchTranscript model = null!;
+        private int eventIndex = 0;
+        private bool closed;
+
+        public TranscriptReader(string workingDir, string inputFilename)
+        {
+            closed = false;
+            this.workingDir = workingDir;
+            transcriptFile = Path.Combine(workingDir, TranscriptConstants.TranscriptFilename);
+            artifactsFolder = Path.Combine(workingDir, TranscriptConstants.ArtifactFolderName);
+
+            if (!Directory.Exists(workingDir)) Directory.CreateDirectory(workingDir);
+            if (File.Exists(transcriptFile) || Directory.Exists(artifactsFolder)) throw new Exception("workingdir not clean");
+
+            LoadModel(inputFilename);
+        }
+
+        public T GetHeader<T>(string key)
+        {
+            CheckClosed();
+            var value = model.Header.Entries.First(e => e.Key == key).Value;
+            return JsonConvert.DeserializeObject<T>(value)!;
+        }
+
+        public void AddHandler<T>(Action<DateTime, T> handler)
+        {
+            CheckClosed();
+            var typeName = typeof(T).FullName;
+            if (string.IsNullOrEmpty(typeName)) throw new Exception("Empty typename for payload");
+
+            handlers.Add(typeName, (utc, s) =>
+            {
+                handler(utc, JsonConvert.DeserializeObject<T>(s)!);
+            });
+        }
+
+        public void Next()
+        {
+            CheckClosed();
+            if (eventIndex >= model.Events.Length) return;
+
+            var @event = model.Events[eventIndex];
+            eventIndex++;
+
+            PlayEvent(@event);
+        }
+
+        public void Close()
+        {
+            CheckClosed();
+            Directory.Delete(workingDir, true);
+            closed = true;
+        }
+
+        private void PlayEvent(OverwatchEvent @event)
+        {
+            if (!handlers.ContainsKey(@event.Type)) return;
+            var handler = handlers[@event.Type];
+
+            handler(@event.Utc, @event.Payload);
+        }
+
+        private void LoadModel(string inputFilename)
+        {
+            ZipFile.ExtractToDirectory(inputFilename, workingDir);
+
+            if (!File.Exists(transcriptFile))
+            {
+                closed = true;
+                throw new Exception("Is not a transcript file. Unzipped to: " + workingDir);
+            }
+
+            model = JsonConvert.DeserializeObject<OverwatchTranscript>(File.ReadAllText(transcriptFile))!;
+        }
+
+        private void CheckClosed()
+        {
+            if (closed) throw new Exception("Transcript has already been written. Cannot modify or write again.");
+        }
+    }
+}
diff --git a/Tools/OverwatchTranscript/TranscriptWriter.cs b/Tools/OverwatchTranscript/TranscriptWriter.cs
new file mode 100644
index 00000000..21cb3725
--- /dev/null
+++ b/Tools/OverwatchTranscript/TranscriptWriter.cs
@@ -0,0 +1,98 @@
+using Newtonsoft.Json;
+using System.IO.Compression;
+
+namespace OverwatchTranscript
+{
+    public interface ITranscriptWriter
+    {
+        void AddHeader(string key, object value);
+        void Add(DateTime utc, object payload);
+        void IncludeArtifact(string filePath);
+        void Write(string outputFilename);
+    }
+
+    public class TranscriptWriter : ITranscriptWriter
+    {
+        private readonly string transcriptFile;
+        private readonly string artifactsFolder;
+        private readonly Dictionary<string, string> header = new Dictionary<string, string>();
+        private readonly SortedList<DateTime, OverwatchEvent> buffer = new SortedList<DateTime, OverwatchEvent>();
+        private readonly string workingDir;
+        private bool closed;
+
+        public TranscriptWriter(string workingDir)
+        {
+            closed = false;
+            this.workingDir = workingDir;
+            transcriptFile = Path.Combine(workingDir, TranscriptConstants.TranscriptFilename);
+            artifactsFolder = Path.Combine(workingDir, TranscriptConstants.ArtifactFolderName);
+
+            if (!Directory.Exists(workingDir)) Directory.CreateDirectory(workingDir);
+            if (File.Exists(transcriptFile) || Directory.Exists(artifactsFolder)) throw new Exception("workingdir not clean");
+        }
+
+        public void Add(DateTime utc, object payload)
+        {
+            CheckClosed();
+            var typeName = payload.GetType().FullName;
+            if (string.IsNullOrEmpty(typeName)) throw new Exception("Empty typename for payload");
+
+            buffer.Add(utc, new OverwatchEvent
+            {
+                Utc = utc,
+                Type = typeName,
+                Payload = JsonConvert.SerializeObject(payload)
+            });
+        }
+
+        public void AddHeader(string key, object value)
+        {
+            CheckClosed();
+            header.Add(key, JsonConvert.SerializeObject(value));
+        }
+
+        public void IncludeArtifact(string filePath)
+        {
+            CheckClosed();
+            if (!File.Exists(filePath)) throw new Exception("File not found: " + filePath);
+            var name = Path.GetFileName(filePath);
+            File.Copy(filePath, Path.Combine(artifactsFolder, name), overwrite: false);
+        }
+
+        public void Write(string outputFilename)
+        {
+            CheckClosed();
+            closed = true;
+
+            var model = new OverwatchTranscript
+            {
+                Header = new OverwatchHeader
+                {
+                    Entries = header.Select(h =>
+                    {
+                        return new OverwatchHeaderEntry
+                        {
+                            Key = h.Key,
+                            Value = h.Value
+                        };
+                    }).ToArray()
+                },
+                Events = buffer.Values.ToArray()
+            };
+
+            header.Clear();
+            buffer.Clear();
+
+            File.WriteAllText(transcriptFile, JsonConvert.SerializeObject(model, Formatting.Indented));
+
+            ZipFile.CreateFromDirectory(workingDir, outputFilename);
+
+            Directory.Delete(workingDir, true);
+        }
+
+        private void CheckClosed()
+        {
+            if (closed) throw new Exception("Transcript has already been written. Cannot modify or write again.");
+        }
+    }
+}