diff --git a/python/ql/lib/semmle/python/dataflow/new/internal/DataFlowDispatch.qll b/python/ql/lib/semmle/python/dataflow/new/internal/DataFlowDispatch.qll
index c717cd7bc97..b04b83be83e 100644
--- a/python/ql/lib/semmle/python/dataflow/new/internal/DataFlowDispatch.qll
+++ b/python/ql/lib/semmle/python/dataflow/new/internal/DataFlowDispatch.qll
@@ -1714,36 +1714,66 @@ private class SummaryPostUpdateNode extends FlowSummaryNode, PostUpdateNodeImpl
  * This is also known as the environment part of a closure.
  *
  * This is used for tracking flow through captured variables.
- *
- * TODO:
- * We might want a synthetic node here, but currently that incurs problems
- * with non-monotonic recursion, because of the use of `resolveCall` in the
- * char pred. This may be solvable by using
- * `CallGraphConstruction::Make` in stead of
- * `CallGraphConstruction::Simple::Make` appropriately.
  */
-class CapturedVariablesArgumentNode extends CfgNode, ArgumentNode {
-  CallNode callNode;
+class SynthCapturedVariablesArgumentNode extends Node, TSynthCapturedVariablesArgumentNode {
+  ControlFlowNode callable;
 
-  CapturedVariablesArgumentNode() {
-    node = callNode.getFunction() and
-    exists(Function target | resolveCall(callNode, target, _) |
-      target = any(VariableCapture::CapturedVariable v).getACapturingScope()
-    )
-  }
+  SynthCapturedVariablesArgumentNode() { this = TSynthCapturedVariablesArgumentNode(callable) }
+
+  /** Gets the `CallNode` corresponding to this captured variables argument node. */
+  CallNode getCallNode() { result.getFunction() = callable }
+
+  /** Gets the `CfgNode` that corresponds to this synthetic node. */
+  CfgNode getUnderlyingNode() { result.asCfgNode() = callable }
+
+  override Scope getScope() { result = callable.getScope() }
+
+  override Location getLocation() { result = callable.getLocation() }
 
   override string toString() { result = "Capturing closure argument" }
+}
 
+/** A captured variables argument node viewed as an argument node. Needed because `argumentOf` is a global predicate. */
+class CapturedVariablesArgumentNodeAsArgumentNode extends ArgumentNode,
+  SynthCapturedVariablesArgumentNode
+{
   override predicate argumentOf(DataFlowCall call, ArgumentPosition pos) {
-    callNode = call.getNode() and
-    pos.isLambdaSelf()
+    exists(CallNode callNode | callNode = this.getCallNode() |
+      callNode = call.getNode() and
+      exists(Function target | resolveCall(callNode, target, _) |
+        target = any(VariableCapture::CapturedVariable v).getACapturingScope()
+      ) and
+      pos.isLambdaSelf()
+    )
+  }
+}
+
+/** A synthetic node representing the values of captured variables after the output has been computed. */
+class SynthCapturedVariablesArgumentPostUpdateNode extends PostUpdateNodeImpl,
+  TSynthCapturedVariablesArgumentPostUpdateNode
+{
+  ControlFlowNode callable;
+
+  SynthCapturedVariablesArgumentPostUpdateNode() {
+    this = TSynthCapturedVariablesArgumentPostUpdateNode(callable)
+  }
+
+  /** Gets the `PostUpdateNode` (for a `CfgNode`) that corresponds to this synthetic node. */
+  PostUpdateNode getUnderlyingNode() { result.getPreUpdateNode().asCfgNode() = callable }
+
+  override string toString() { result = "[post] Capturing closure argument" }
+
+  override Scope getScope() { result = callable.getScope() }
+
+  override Location getLocation() { result = callable.getLocation() }
+
+  override SynthCapturedVariablesArgumentNode getPreUpdateNode() {
+    result = TSynthCapturedVariablesArgumentNode(callable)
   }
 }
 
 /** A synthetic node representing the values of variables captured by a comprehension. */
-class SynthCompCapturedVariablesArgumentNode extends Node, TSynthCompCapturedVariablesArgumentNode,
-  ArgumentNode
-{
+class SynthCompCapturedVariablesArgumentNode extends Node, TSynthCompCapturedVariablesArgumentNode {
   Comp comp;
 
   SynthCompCapturedVariablesArgumentNode() { this = TSynthCompCapturedVariablesArgumentNode(comp) }
@@ -1755,7 +1785,11 @@ class SynthCompCapturedVariablesArgumentNode extends Node, TSynthCompCapturedVar
   override Location getLocation() { result = comp.getLocation() }
 
   Comp getComprehension() { result = comp }
+}
 
+class SynthCompCapturedVariablesArgumentNodeAsArgumentNode extends SynthCompCapturedVariablesArgumentNode,
+  ArgumentNode
+{
   override predicate argumentOf(DataFlowCall call, ArgumentPosition pos) {
     call.(ComprehensionCall).getComprehension() = comp and
     pos.isLambdaSelf()
diff --git a/python/ql/lib/semmle/python/dataflow/new/internal/DataFlowPrivate.qll b/python/ql/lib/semmle/python/dataflow/new/internal/DataFlowPrivate.qll
index 2322539995b..9866bd00964 100644
--- a/python/ql/lib/semmle/python/dataflow/new/internal/DataFlowPrivate.qll
+++ b/python/ql/lib/semmle/python/dataflow/new/internal/DataFlowPrivate.qll
@@ -1128,6 +1128,14 @@ predicate nodeIsHidden(Node n) {
   n instanceof SynthCaptureNode
   or
   n instanceof SynthCapturedVariablesParameterNode
+  or
+  n instanceof SynthCapturedVariablesArgumentNode
+  or
+  n instanceof SynthCapturedVariablesArgumentPostUpdateNode
+  or
+  n instanceof SynthCompCapturedVariablesArgumentNode
+  or
+  n instanceof SynthCompCapturedVariablesArgumentPostUpdateNode
 }
 
 class LambdaCallKind = Unit;
diff --git a/python/ql/lib/semmle/python/dataflow/new/internal/DataFlowPublic.qll b/python/ql/lib/semmle/python/dataflow/new/internal/DataFlowPublic.qll
index d14cac5a4cd..532f7b23e4c 100644
--- a/python/ql/lib/semmle/python/dataflow/new/internal/DataFlowPublic.qll
+++ b/python/ql/lib/semmle/python/dataflow/new/internal/DataFlowPublic.qll
@@ -121,6 +121,20 @@ newtype TNode =
     f = any(VariableCapture::CapturedVariable v).getACapturingScope() and
     exists(TFunction(f))
   } or
+  /**
+   * A synthetic node representing the values of the variables captured
+   * by the callable being called.
+   */
+  TSynthCapturedVariablesArgumentNode(ControlFlowNode callable) {
+    callable = any(CallNode c).getFunction()
+  } or
+  /**
+   * A synthetic node representing the values of the variables captured
+   * by the callable being called, after the output has been computed.
+   */
+  TSynthCapturedVariablesArgumentPostUpdateNode(ControlFlowNode callable) {
+    callable = any(CallNode c).getFunction()
+  } or
   /** A synthetic node representing the values of variables captured by a comprehension. */
   TSynthCompCapturedVariablesArgumentNode(Comp comp) {
     comp.getFunction() = any(VariableCapture::CapturedVariable v).getACapturingScope()
diff --git a/python/ql/lib/semmle/python/dataflow/new/internal/VariableCapture.qll b/python/ql/lib/semmle/python/dataflow/new/internal/VariableCapture.qll
index a7b3b9ceaeb..5ed365a8e56 100644
--- a/python/ql/lib/semmle/python/dataflow/new/internal/VariableCapture.qll
+++ b/python/ql/lib/semmle/python/dataflow/new/internal/VariableCapture.qll
@@ -114,6 +114,12 @@ private Flow::ClosureNode asClosureNode(Node n) {
     result.(Flow::ExprNode).getExpr().getNode() = comp
   )
   or
+  // For captured variable argument nodes (and their post-update variants), we use the closure node
+  // for the underlying node.
+  result = asClosureNode(n.(SynthCapturedVariablesArgumentNode).getUnderlyingNode())
+  or
+  result = asClosureNode(n.(SynthCapturedVariablesArgumentPostUpdateNode).getUnderlyingNode())
+  or
   // TODO: Should the `Comp`s above be excluded here?
   result.(Flow::ExprNode).getExpr() = n.(CfgNode).getNode()
   or